<!--    Elsevier Common Element Pool v1.6.0p1
        
        Copyright © 2002-2018 Elsevier B.V.
        This is open access material under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

        Documentation available at https://www.elsevier.com/locate/xml
-->
<!--    Typical invocation:

        <!ENTITY % common.ent
            PUBLIC "-//ES//ELEMENTS common element pool version 1.6.0//EN//XML"
            "common160.ent">
        %common.ent;
-->

<!-- namespaces and public identifiers -->

<!ENTITY % ESCE.xmlns	"'https://www.elsevier.com/xml/common/dtd'" >
<!ENTITY % ESSA.xmlns   "'https://www.elsevier.com/xml/common/struct-aff/dtd'" >
<!ENTITY % ESSB.xmlns   "'https://www.elsevier.com/xml/common/struct-bib/dtd'" >
<!ENTITY % ESTB.xmlns   "'https://www.elsevier.com/xml/common/table/dtd'" >
<!ENTITY % XLINK.xmlns  "'http://www.w3.org/1999/xlink'" >
<!ENTITY % CALS.xmlns	"'https://www.elsevier.com/xml/common/cals/dtd'" >

<!-- notations -->

<!NOTATION TEXT        PUBLIC "-//ES//NOTATION text format//EN"
                       "https://www.elsevier.com/xml/common/dtd/notation/text" >
<!NOTATION IMAGE       PUBLIC "-//ES//NOTATION image format//EN"
                       "https://www.elsevier.com/xml/common/dtd/notation/image" >
<!NOTATION AUDIO       PUBLIC "-//ES//NOTATION audio format//EN"
                       "https://www.elsevier.com/xml/common/dtd/notation/audio" >
<!NOTATION VIDEO       PUBLIC "-//ES//NOTATION video format//EN"
                       "https://www.elsevier.com/xml/common/dtd/notation/video" >
<!NOTATION APPLICATION PUBLIC "-//ES//NOTATION application format//EN"
                       "https://www.elsevier.com/xml/common/dtd/notation/application" >
<!NOTATION XML         PUBLIC "-//ES//NOTATION XML format//EN"
                       "https://www.elsevier.com/xml/common/dtd/notation/xml" >

<!-- element group entities -->

<!ENTITY % font-change      "ce:bold|ce:italic|ce:monospace|ce:sans-serif|ce:small-caps" >
<!ENTITY % text-effect      "%font-change;|ce:sup|ce:inf|ce:underline|ce:cross-out|ce:hsp|ce:vsp" >
<!ENTITY % text-objects     "ce:anchor|ce:grant-sponsor|ce:grant-number" >
<!ENTITY % lists            "ce:def-list|ce:list" >
<!ENTITY % display          "ce:display|ce:displayed-quote|ce:enunciation" >
<!ENTITY % cross-ref        "ce:cross-ref|ce:intra-ref" >
<!ENTITY % cross-refs       "ce:cross-refs|ce:intra-refs" >
<!ENTITY % cross-ref-s      "%cross-ref;|%cross-refs;" >
<!ENTITY % inter-ref-s      "ce:inter-ref|ce:inter-refs" >
<!ENTITY % cell-borders     "tb:top-border|tb:left-border|tb:bottom-border|tb:right-border" >

<!-- content entities, local variants defined in DTDs -->

<!ENTITY % local.string.data     "" >
<!ENTITY % local.richstring.data "" >
<!ENTITY % local.text.data       "" >
<!ENTITY % local.textfn.data     "" >
<!ENTITY % local.textref.data    "" >
<!ENTITY % local.nondisplay.data "" >
<!ENTITY % local.note.data       "" >
<!ENTITY % local.cell.data       "" >
<!ENTITY % local.spar.data       "" >
<!ENTITY % local.par.data        "" >
<!ENTITY % string.data      "#PCDATA %local.string.data;" >
<!ENTITY % richstring.data  "#PCDATA|ce:glyph|%text-effect;|ce:inline-figure
                             %local.richstring.data;" >
<!ENTITY % math             "mml:math|ce:math" >
<!ENTITY % text.data        "%richstring.data;|%math; %local.text.data;" >
<!ENTITY % textlink.data    "%text.data;|ce:inter-ref" >
<!ENTITY % textfn.data      "%text.data;|ce:footnote|%cross-ref-s; %local.textfn.data;" >
<!ENTITY % textref.data     "%text.data;|%cross-ref-s;|%inter-ref-s; %local.textref.data;" >
<!ENTITY % nondisplay.data  "%textref.data;|ce:footnote|ce:anchor %local.nondisplay.data;" >
<!ENTITY % cell.data        "%textref.data;|%display;|%lists;|%cell-borders;|tb:alignmark|ce:br
                             %local.cell.data;" >
<!ENTITY % note.data        "%textref.data;|%display;|%lists;|%text-objects; %local.note.data;" >
<!ENTITY % spar.data        "%textref.data;|%display;|%lists;|ce:footnote|%text-objects;
                             %local.spar.data;" >
<!ENTITY % par.data         "%textref.data;|ce:float-anchor|%display;|%lists;|ce:footnote|%text-objects;
                             %local.par.data;" >

<!-- content model entities -->

<!ENTITY % copyright        "ce:copyright, ce:copyright-line?" >
<!ENTITY % name             "( ( ce:given-name, ce:surname ) | ( ce:surname, ce:given-name? ) ),
                               ce:suffix?, ce:alt-name*" >
<!ENTITY % parsec           "( ce:para | ce:section )+" >
<!ENTITY % titles           "( ce:title, ce:subtitle?, ( ce:alt-title, ce:alt-subtitle? )* )" >
<!ENTITY % sb.titles        "( ( sb:title, sb:translated-title? ) | sb:translated-title )" >
<!ENTITY % glossary-entry-refs "( ce:see+ | ( ce:cross-ref | ce:intra-ref | ce:inter-ref )+ )" >
<!ENTITY % index-entry-refs    "( ce:see+ | ( ce:cross-ref | ce:intra-ref )+ )"  >

<!-- attribute type entities -->

<!ENTITY % abstract-class   "(author|editor|graphical|teaser|author-highlights|editor-highlights|sda)" >
<!ENTITY % copyright-type   "(full-transfer|limited-transfer|no-transfer|unknown|us-gov|crown|
                              society|other|joint|free-of-copyright)" >
<!ENTITY % e-address-type   "(email|url|social-media)" >
<!ENTITY % hline            "(bar|tcub|bcub|tsqb|bsqb|circ|tilde|larr|rarr|harr|lharu|rharu|
                              tpar|bpar)" >
<!ENTITY % language-type    "(en|non-en|iso|unknown)" >
<!ENTITY % loc              "(pre|post)" >
<!ENTITY % style            "(s|d|t|da|dot|b|bl|n)" >
<!ENTITY % view             "(compact|standard|extended|compact-standard|standard-extended|all)" >
<!ENTITY % vline            "(lpar|rpar|lsqb|rsqb|lcub|rcub|lang|rang|vb|sol|bsol|lceil|rceil|
                              lfloor|rfloor|dharr|uharr|darr|uarr|varr)" >

<!-- attribute type entities iso -->

<!-- see links at http://www.w3.org/TR/REC-xml#sec-lang-tag -->
<!ENTITY % iso639-cur       "aa|ab|af|am|ar|as|ay|az|ba|be|bg|bh|bi|bn|bo|br|ca|co|cs|cy|da|de|dz|
  el|en|eo|es|et|eu|fa|fi|fj|fo|fr|fy|ga|gd|gl|gn|gu|ha|he|hi|hr|hu|hy|ia|id|ie|ik|is|it|ja|jw|ka|
  kk|kl|km|kn|ko|ks|ku|ky|la|ln|lo|lt|lv|mg|mi|mk|ml|mn|mo|mr|ms|mt|my|na|ne|nl|no|oc|om|or|pa|pl|
  ps|pt|qu|rm|rn|ro|ru|rw|sa|sd|sg|si|sk|sl|sm|sn|so|sq|sr|ss|st|su|sv|sw|ta|te|tg|th|ti|tk|tl|tn|
  to|tr|ts|tt|tw|uk|ur|uz|vi|vo|wo|xh|yi|yo|zh|zu" >
<!ENTITY % iso639-obs       "" >
<!ENTITY % iso639           "(%iso639-cur; %iso639-obs;)" >

<!ENTITY % glyph-names      '(S|bigdot|btmlig|camb|ctl|dbnd|dbnd6|dcurt|dlcorn|drcorn|ggrave|hbar|
  heng|herma|hris|hriss|hrttrh|ht|jnodot|lbd2bd|lbd2td|lbond2|lbond3|lozf|lozfl|lozfr|lris|
  lriss|ncurt|nsmid|nspar|pSlash|pdbdtd|pdbond|pent|phktp|ptbdbd|ptbdtd|qbnd|qbnd6|rad|rbd2bd|
  rbd2td|rbond2|rbond3|refhrl|resmck|risfla|risfls|sbnd|sbw|smid|spar|sqfb|sqfne|sqfsw|sqft|tbnd|
  tbnd6|tcurt|trisla|trnomeg)' >

<!-- attribute group entities -->

<!-- optref: optional target for a cross-ref or intra-ref -->
<!-- reqref: target for a cross-ref or intra-ref -->
<!-- link:   optional target for an external link -->
<!ENTITY % common-link.att        "id      ID       #IMPLIED" >
<!ENTITY % common-optref-link.att "id      ID       #IMPLIED" >
<!ENTITY % common-optref.att      "id      ID       #IMPLIED" >
<!ENTITY % common-reqref-link.att "id      ID       #REQUIRED" >
<!ENTITY % common-reqref.att      "id      ID       #REQUIRED" >
<!ENTITY % common-role.att        "role    CDATA    #IMPLIED" >
<!ENTITY % common-altimg.att      "altimg  CDATA    #IMPLIED" >
<!ENTITY % common-reqaltimg.att   "altimg  CDATA    #REQUIRED" >
<!ENTITY % common-view.att        "view    %view;   'all'" >
<!ENTITY % external-file.att      "locator ENTITY   #REQUIRED">

<!-- general purpose elements -->

<!ELEMENT   ce:text             ( %textlink.data; )* >
<!ATTLIST   ce:text
                %common-link.att; >
<!ELEMENT   ce:textfn           ( %textfn.data; )* >
<!ATTLIST   ce:textfn
                %common-link.att; >
<!ELEMENT   ce:textref          ( %textref.data; )* >
<!ATTLIST   ce:textref
                %common-link.att; >
<!ELEMENT   ce:label            ( %text.data; )* >
<!ELEMENT   ce:section-title    ( %nondisplay.data; )* >
<!ATTLIST   ce:section-title
                %common-link.att;
                %common-role.att; >

<!-- information about the item -->

<!ELEMENT   ce:pii              ( %string.data; )* >
<!ELEMENT   ce:doi              ( %string.data; )* >
<!ELEMENT   ce:isbn             ( %string.data; )* >
<!ELEMENT   ce:issn             ( %string.data; )* >
<!ELEMENT   ce:article-number   ( %string.data; )* >
<!ELEMENT   ce:document-thread  ( ce:refers-to-document+ )>
<!ELEMENT   ce:refers-to-document ( ce:doi | ( ce:pii, ce:doi? ) )>
<!ATTLIST   ce:refers-to-document
                %common-link.att;
                %common-role.att; >
<!ELEMENT   ce:copyright        ( %string.data; )* >
<!ATTLIST   ce:copyright
                type            %copyright-type;    #REQUIRED
                year            NMTOKEN             #REQUIRED>
<!ELEMENT   ce:copyright-line   ( %richstring.data; )* >
<!ELEMENT   ce:imprint          ( %richstring.data; )* >
<!ELEMENT   ce:edition          ( %string.data; )* >
<!ELEMENT   ce:doctopics        ( ce:doctopic+ )>
<!ELEMENT   ce:doctopic         ( ce:text, ce:doctopic? )>
<!ATTLIST   ce:doctopic
                %common-link.att;
                %common-role.att; >
<!ELEMENT   ce:preprint         ( ce:inter-ref )>
<!ELEMENT   ce:associated-resource ( ce:inter-ref )>

<!-- article footnote -->

<!ELEMENT   ce:article-footnote ( ce:label?, ce:note-para+ )>
<!ATTLIST   ce:article-footnote
                %common-role.att; >

<!-- article dochead, article title, alternative-language title, subtitle -->

<!ELEMENT   ce:markers          ( ce:marker+ )>
<!ELEMENT   ce:marker           EMPTY >
<!ATTLIST   ce:marker
                name            CDATA               #REQUIRED
                alt             CDATA               #REQUIRED
                %common-reqaltimg.att;
                altimg-small    CDATA               #REQUIRED
                %common-role.att; >
<!ELEMENT   ce:dochead          ( ce:textfn, ce:dochead? )>
<!ATTLIST   ce:dochead
                %common-link.att; >
<!ELEMENT   ce:title            ( %textfn.data; )* >
<!ATTLIST   ce:title
                %common-link.att; >
<!ELEMENT   ce:alt-title        ( %textfn.data; )* >
<!ATTLIST   ce:alt-title
                %common-link.att;
                xml:lang        %iso639;            #REQUIRED>
<!ELEMENT   ce:subtitle         ( %textfn.data; )* >
<!ATTLIST   ce:subtitle
                %common-link.att; >
<!ELEMENT   ce:alt-subtitle     ( %textfn.data; )* >
<!ATTLIST   ce:alt-subtitle
                %common-link.att;
                xml:lang        %iso639;            #REQUIRED>
<!ELEMENT   ce:short-title      ( %text.data; )* >
<!ATTLIST   ce:short-title
                %common-link.att; >

<!-- presented by/at, dedication -->

<!ELEMENT   ce:presented        ( %textfn.data; )* >
<!ATTLIST   ce:presented
                %common-link.att; >
<!ELEMENT   ce:dedication       ( %textfn.data; )* >
<!ATTLIST   ce:dedication
                %common-link.att;
                %common-role.att; >

<!-- author group -->

<!ELEMENT   ce:author-group     ( ( ce:collaboration | ce:author | ce:text )+,
                                  ce:affiliation*, ce:correspondence*, ce:footnote* )>
<!ATTLIST   ce:author-group
                %common-link.att;
                %common-role.att; >

<!ELEMENT   ce:collaboration    ( ce:indexed-name?, ce:text, (%cross-ref;)*, ce:collab-aff?,
                                  ce:e-address*, ce:author-group* )>
                                    <!-- only 1-1 xrefs to affiliation,correspondence,footnote -->
<!ATTLIST   ce:collaboration
                %common-link.att;
                %common-role.att;
                collaboration-id  CDATA  #IMPLIED >
<!ELEMENT   ce:collab-aff       ( %text.data; )* >

<!ELEMENT   ce:author           ( ce:initials?, ce:indexed-name?, ce:degrees?, %name;, ce:degrees?,
                                  ce:ranking?, ce:roles?, ce:contributor-role*,
                                  ce:alias?,
                                  (%cross-ref;)*, ce:e-address*, ce:link? )>
                                    <!-- only 1-1 xrefs to affiliation,correspondence,footnote -->
<!ATTLIST   ce:author
                %common-link.att;
                %common-role.att;
                orcid           CDATA               #IMPLIED
                author-id       CDATA               #IMPLIED
                biographyid     IDREF               #IMPLIED>
<!ELEMENT   ce:initials         ( %string.data; )* >
<!ELEMENT   ce:indexed-name     ( %string.data; )* >
<!ELEMENT   ce:degrees          ( %richstring.data; )* >
<!ELEMENT   ce:given-name       ( %richstring.data; )* >
<!ELEMENT   ce:surname          ( %text.data; )* >
<!ELEMENT   ce:suffix           ( %richstring.data; )* >
<!ELEMENT   ce:alt-name         ( %richstring.data; )* >
<!ELEMENT   ce:ranking          ( %richstring.data; )* >
<!ELEMENT   ce:roles            ( %richstring.data; )* >
<!ELEMENT   ce:contributor-role ( %string.data; )* >
<!ATTLIST   ce:contributor-role
                role            CDATA               #IMPLIED
                degree          CDATA               #IMPLIED>

<!ELEMENT   ce:alias            ( %string.data; )* >

<!ELEMENT   ce:correspondence   ( ce:label, ce:text, sa:affiliation? )>
<!ATTLIST   ce:correspondence
                %common-reqref.att; >

<!ELEMENT   ce:e-address        ( %text.data; )* >
<!ATTLIST   ce:e-address
                %common-link.att;
                type            %e-address-type;    "email"
                xlink:href      CDATA               #IMPLIED>

<!ELEMENT   ce:affiliation      ( ce:label?, ce:textfn, sa:affiliation?, ce:source-text? )>
<!ATTLIST   ce:affiliation
                %common-optref-link.att;
                %common-role.att;
                affiliation-id  CDATA               #IMPLIED>

<!-- structured affiliation (in name space ESSA) -->

<!ELEMENT   sa:affiliation      ( sa:organization*, sa:address-line*,
                                  sa:city?, sa:state?, sa:postal-code?, sa:country? )>
<!ATTLIST   sa:affiliation
                xmlns:sa        CDATA               #FIXED  %ESSA.xmlns; >

<!ELEMENT   sa:organization     ( %richstring.data; )* >
<!ELEMENT   sa:address-line     ( %text.data; )* >
<!ELEMENT   sa:city             ( %text.data; )* >
<!ELEMENT   sa:state            ( %text.data; )* >
<!ELEMENT   sa:postal-code      ( %string.data; )* >
<!ELEMENT   sa:country          ( %text.data; )* >

<!-- editors -->

<!ELEMENT   ce:editors          ( ce:author-group+ )>
<!ATTLIST   ce:editors
                %common-role.att; >

<!-- article history -->

<!ELEMENT   ce:date-received    EMPTY>
<!ATTLIST   ce:date-received
                day             NMTOKEN             #IMPLIED
                month           NMTOKEN             #REQUIRED
                year            NMTOKEN             #REQUIRED>
<!ELEMENT   ce:date-revised     EMPTY>
<!ATTLIST   ce:date-revised
                day             NMTOKEN             #IMPLIED
                month           NMTOKEN             #REQUIRED
                year            NMTOKEN             #REQUIRED>
<!ELEMENT   ce:date-accepted    EMPTY>
<!ATTLIST   ce:date-accepted
                day             NMTOKEN             #IMPLIED
                month           NMTOKEN             #REQUIRED
                year            NMTOKEN             #REQUIRED
                %common-role.att; >

<!ELEMENT   ce:miscellaneous    ( %text.data; )* >
<!ATTLIST   ce:miscellaneous
                %common-link.att;
                %common-role.att; >

<!-- abstract -->

<!ELEMENT   ce:abstract         ( ce:section-title?, ce:abstract-sec+, ce:figure? )>
<!ATTLIST   ce:abstract
                %common-link.att;
                %common-view.att;
                class           %abstract-class;    "author"
                xml:lang        %iso639;            #IMPLIED>
<!ELEMENT   ce:abstract-sec     ( ce:section-title?, ce:simple-para+ )>
<!ATTLIST   ce:abstract-sec
                %common-link.att;
                %common-role.att;
                %common-view.att; >

<!-- keywords -->

<!ELEMENT   ce:keywords         ( ce:section-title?, ce:keyword+ )>
<!ATTLIST   ce:keywords
                %common-link.att;
                %common-view.att;
                class           CDATA               "keyword"
                xml:lang        %iso639;            #IMPLIED>
<!ELEMENT   ce:keyword          ( ce:text, ce:keyword* )>
<!ATTLIST   ce:keyword
                %common-link.att; >

<!-- stereochemistry abstracts -->

<!ELEMENT   ce:stereochem       ( ce:compound-struct, ( ce:compound-formula |
                                  ( ce:compound-name, ce:compound-formula? ) ), ce:compound-info )>
<!ATTLIST   ce:stereochem
                %common-optref-link.att;
                %common-role.att;
                %common-view.att; >
<!ELEMENT   ce:compound-struct  ( ce:link )>
<!ELEMENT   ce:compound-name    ( %text.data; )* >
<!ELEMENT   ce:compound-formula ( %text.data; )* >
<!ELEMENT   ce:compound-info    ( ce:list-item+ )>

<!-- nomenclature -->

<!ELEMENT   ce:nomenclature     ( ce:section-title?, ce:def-list+ )>
<!ATTLIST   ce:nomenclature
                %common-optref-link.att;
                %common-role.att;
                %common-view.att; >

<!-- article body -->

<!ELEMENT   ce:salutation       ( %text.data; )* >
<!ELEMENT   ce:sections         ( %parsec; )>
<!ELEMENT   ce:appendices       ( ce:section+ )>
<!ATTLIST   ce:appendices
                %common-view.att; >
<!ELEMENT   ce:section          ( ( ( ce:section-title | ( ce:label, ce:section-title? ) ),
                                  %parsec; ) | ce:section+ )>
<!ATTLIST   ce:section
                %common-optref-link.att;
                %common-role.att;
                %common-view.att; >
<!ELEMENT   ce:para             ( %par.data; )* >
<!ATTLIST   ce:para
                %common-link.att;
                %common-role.att;
                %common-view.att; >
<!ELEMENT   ce:simple-para      ( %spar.data; )* >
<!ATTLIST   ce:simple-para
                %common-link.att;
                %common-role.att;
                %common-view.att; >
<!ELEMENT   ce:note-para        ( %note.data; )* >
<!ATTLIST   ce:note-para
                %common-link.att;
                %common-role.att;
                %common-view.att; >
<!ELEMENT   ce:intro            ( ce:para+ )>
<!ATTLIST   ce:intro
                %common-link.att;
                %common-role.att;
                %common-view.att; >

<!-- acknowledgement -->

<!ELEMENT   ce:acknowledgment   ( ce:section-title?, %parsec; )>
<!ATTLIST   ce:acknowledgment
                %common-link.att;
                %common-role.att;
                %common-view.att; >
                
<!ELEMENT   ce:conflict-of-interest  ( ce:section-title?, ce:para+ )>
<!ATTLIST   ce:conflict-of-interest
                %common-reqref-link.att;
                %common-role.att;
                %common-view.att; >

<!ELEMENT   ce:data-availability  ( ce:section-title?, ce:para+ )>
<!ATTLIST   ce:data-availability
                %common-reqref-link.att;
                %common-role.att;
                %common-view.att; >

<!-- source text -->

<!ELEMENT   ce:source-text      ( %string.data; )*>
<!ATTLIST   ce:source-text
                %common-reqref-link.att; >

<!-- bibliography -->

<!ELEMENT   ce:bibliography     ( ce:section-title, ce:intro?, ce:bibliography-sec+ )>
<!ATTLIST   ce:bibliography
                %common-optref.att;
                %common-role.att;
                %common-view.att; >
<!--
<!ELEMENT   ce:bibliography-sec ( ce:section-title?,
                                  ( ( ce:bib-reference+, ce:bibliography-sec* ) | ce:bibliography-sec* ) )>
-->
<!ELEMENT   ce:bibliography-sec ( ce:section-title?, ce:bib-reference*, ce:bibliography-sec* )>
<!ATTLIST   ce:bibliography-sec
                %common-optref.att;
                %common-role.att;
                %common-view.att; >
<!-- 
<!ELEMENT   ce:bib-reference    ( ce:label, ( ce:note |
                                  ( ( sb:reference | ce:other-ref )+, ce:note? ) ) )>
<!ELEMENT   ce:bib-reference    ( ce:label, ( ce:note |
                                  ( ( sb:reference | ce:other-ref )+, ce:note? ) ),
                                  ce:source-text? )>
-->
<!ELEMENT   ce:bib-reference    ( ce:label, ( ce:note |
                                  ( ( ( sb:reference | ce:other-ref ), ce:source-text? )+, ce:note? ) ) )>
<!ATTLIST   ce:bib-reference
                %common-reqref-link.att;
                %common-role.att;  >
<!ELEMENT   ce:note             ( ce:simple-para+ )>

<!-- structured bibliographic reference (in name space ESSB) -->

<!ELEMENT   sb:reference        ( ce:label?, sb:comment?, ( sb:contribution, sb:comment? )?,
                                  ( sb:host, sb:comment? )+ )>
<!ATTLIST   sb:reference
                %common-optref-link.att;
                xmlns:sb        CDATA               #FIXED  %ESSB.xmlns; >

<!ELEMENT   sb:contribution     ( sb:authors?, (%sb.titles;)? )>
<!ATTLIST   sb:contribution
                langtype        %language-type;     "en"
                xml:lang        %iso639;            #IMPLIED>

<!ELEMENT   sb:host             ( ( ( ( sb:issue | sb:book | sb:edited-book ), sb:pages? ) | sb:e-host ),
                                  sb:article-number?, ce:doi? )>

<!ELEMENT   sb:comment          ( %nondisplay.data; )* >

<!ELEMENT   sb:authors          ( ( sb:collaboration | ( ( sb:author, sb:et-al? ) | sb:ellipsis ) )+ )>
<!ELEMENT   sb:collaboration    ( %text.data; )* >
<!ELEMENT   sb:author           ( %name; )>
<!ATTLIST   sb:author
                orcid           CDATA               #IMPLIED>
<!ELEMENT   sb:et-al            EMPTY>
<!ELEMENT   sb:ellipsis         EMPTY>
<!ELEMENT   sb:title            ( sb:maintitle, sb:subtitle? )>
<!ELEMENT   sb:translated-title ( sb:maintitle, sb:subtitle? )>
<!ELEMENT   sb:maintitle        ( %text.data; )* >
<!ELEMENT   sb:subtitle         ( %text.data; )* >
<!ELEMENT   sb:issue            ( sb:editors?, (%sb.titles;)?, sb:conference?,
                                  sb:series, sb:issue-nr?, sb:date )>
<!ELEMENT   sb:conference       ( %text.data; )* >
<!ELEMENT   sb:editors          ( ( ( sb:editor, sb:et-al? ) | sb:ellipsis )+ )>
<!ELEMENT   sb:editor           ( %name; )>
<!ATTLIST   sb:editor
                orcid           CDATA               #IMPLIED>
<!ELEMENT   sb:series           ( (%sb.titles;)?, sb:issn?, sb:volume-nr? )>
<!ELEMENT   sb:volume-nr        ( %richstring.data; )* >
<!ELEMENT   sb:issue-nr         ( %richstring.data; )* >
<!ELEMENT   sb:date             ( %richstring.data; )* >
<!ELEMENT   sb:pages            ( sb:first-page, sb:last-page? )>
<!ELEMENT   sb:first-page       ( %richstring.data; )* >
<!ELEMENT   sb:last-page        ( %richstring.data; )* >
<!ELEMENT   sb:book             ( (%sb.titles;)?, sb:edition?, sb:book-series?, sb:date+,
                                  sb:publisher?, sb:isbn? )>
<!ATTLIST   sb:book
                class           CDATA               #IMPLIED>
<!ELEMENT   sb:edition          ( %richstring.data; )* >
<!ELEMENT   sb:publisher        ( sb:name, sb:location? )>
<!ELEMENT   sb:name             ( %richstring.data; )* >
<!ELEMENT   sb:location         ( %richstring.data; )* >
<!ELEMENT   sb:edited-book      ( sb:editors?, (%sb.titles;)?, sb:conference?, sb:edition?,
                                  sb:book-series?, sb:date+, sb:publisher?, sb:isbn? )>
<!ELEMENT   sb:book-series      ( sb:editors?, sb:series )>
<!ELEMENT   sb:e-host           ( sb:publisher?, ce:inter-ref?, sb:version?, sb:date?, sb:date-accessed* )>
<!ELEMENT   sb:issn             ( %string.data; )* >
<!ELEMENT   sb:isbn             ( %string.data; )* >
<!ELEMENT   sb:article-number   ( %string.data; )* >
<!ELEMENT   sb:version          ( %string.data; )* >
<!ELEMENT   sb:date-accessed    EMPTY>
<!ATTLIST   sb:date-accessed
                day             NMTOKEN             #IMPLIED
                month           NMTOKEN             #REQUIRED
                year            NMTOKEN             #REQUIRED>

<!-- unstructured bibliographic reference -->

<!ELEMENT   ce:other-ref        ( ce:label?, ce:textref )>
<!ATTLIST   ce:other-ref
                %common-optref-link.att; >

<!-- further reading -->

<!ELEMENT   ce:further-reading  ( ce:section-title?, ce:intro?, ce:further-reading-sec+ )>
<!ATTLIST   ce:further-reading
                %common-optref.att;
                %common-role.att;
                %common-view.att; >
<!ELEMENT   ce:further-reading-sec ( ce:section-title?, ( ce:para | ce:bib-reference )+, ce:further-reading-sec* )>
<!ATTLIST   ce:further-reading-sec
                %common-optref.att;
                %common-role.att;
                %common-view.att; >

<!-- glossary -->

<!ELEMENT   ce:glossary         ( ce:section-title?, ce:intro?, ce:glossary-sec+ )>
<!ATTLIST   ce:glossary
                %common-optref.att;
                %common-role.att;
                %common-view.att; >
<!ELEMENT   ce:glossary-sec     ( ce:section-title?, ce:intro?, ce:glossary-entry+ )>
<!ATTLIST   ce:glossary-sec
                %common-optref.att;
                %common-role.att;
                %common-view.att; >
<!ELEMENT   ce:glossary-entry   ( ce:indexed-name?, ce:glossary-heading, ce:glossary-def*,
                                  ( %glossary-entry-refs; )?,
                                  ( ce:see-also | ce:glossary-entry | ce:reader-see )* )>
<!ATTLIST   ce:glossary-entry
                %common-optref-link.att;
                %common-role.att; >
<!ELEMENT   ce:glossary-heading ( %textref.data; )* >
<!ELEMENT   ce:glossary-def     ( %note.data; )* >
<!ATTLIST   ce:glossary-def
                %common-link.att; >


<!-- index -->
<!ELEMENT   ce:index            ( ce:section-title?, ce:intro?, ce:index-sec+ )>
<!ATTLIST   ce:index
                %common-optref.att;
                %common-role.att;
                %common-view.att; >
<!ELEMENT   ce:index-sec        ( ce:section-title?, ce:intro?, ce:index-entry+ )>
<!ATTLIST   ce:index-sec
                %common-optref.att;
                %common-role.att;
                %common-view.att; >
<!ELEMENT   ce:index-entry      ( ce:indexed-name?, ce:index-heading,
                                  ( %index-entry-refs; )?,
                                  ( ce:see-also | ce:index-entry | ce:reader-see )* )>
<!ATTLIST   ce:index-entry
                %common-optref-link.att;
                %common-role.att; >

<!ELEMENT   ce:index-heading    ( %textref.data; )* >

<!ELEMENT   ce:see              ( %text.data; )* >
<!ATTLIST   ce:see
                refid           IDREF               #REQUIRED>

<!ELEMENT   ce:see-also         ( %text.data; )* >
<!ATTLIST   ce:see-also
                refid           IDREF               #REQUIRED>

<!ELEMENT   ce:reader-see       ( %text.data; )* >

<!-- index flag -->

<!ELEMENT   ce:index-flag       ( ce:index-flag-term, ce:index-flag-see?,
                                  ( ce:index-flag-see-also | ce:index-flag )* )>
<!ATTLIST   ce:index-flag
                 %common-reqref.att;
                 %common-role.att; >
<!ELEMENT   ce:index-flag-term  ( %text.data; )* >
<!ELEMENT   ce:index-flag-see   ( %text.data; )* >
<!ELEMENT   ce:index-flag-see-also ( %text.data; )* >

<!-- biography -->

<!ELEMENT   ce:biography        ( ce:link?, ce:simple-para+ )>
<!ATTLIST   ce:biography
                %common-optref.att;
                %common-role.att;
                %common-view.att; >

<!-- footnote  -->

<!ELEMENT   ce:footnote         ( ce:label, ce:note-para+ )>
<!ATTLIST   ce:footnote
                %common-reqref.att;
                %common-role.att; >

<!-- anchor in text, the target of e.g. a cross-ref -->

<!ELEMENT   ce:anchor           ( %richstring.data; )* >
<!ATTLIST   ce:anchor
                %common-reqref-link.att;
                %common-role.att; >

<!-- displayed quotation -->

<!ELEMENT   ce:displayed-quote  ( ce:simple-para+, ce:source? )>
<!ATTLIST   ce:displayed-quote
                %common-link.att;
                %common-role.att; >

<!-- enunciation -->

<!ELEMENT   ce:enunciation      ( ce:label, ce:section-title?, ce:para+ )>
<!ATTLIST   ce:enunciation
                %common-optref-link.att;
                %common-role.att; >

<!-- reference to an external entity -->

<!ELEMENT   ce:link             EMPTY>
<!ATTLIST   ce:link
                %common-link.att;
                %external-file.att;
                xlink:type      (simple)            #IMPLIED
                xlink:role      CDATA               #IMPLIED
                xlink:href      CDATA               #IMPLIED>

<!-- reference to an external lower-level doctype -->

<!ELEMENT   ce:include-item     ( ce:pii, ce:doi?, ( %titles; )?,
                                  ( ce:pages* | ce:article-number ) )>
<!ATTLIST   ce:include-item
                %common-role.att;
                %common-view.att; >
<!ELEMENT   ce:pages            ( ce:first-page, ce:last-page? )>
<!ELEMENT   ce:first-page       ( %richstring.data; )* >
<!ELEMENT   ce:last-page        ( %richstring.data; )* >

<!-- reference to objects in this document -->

<!ELEMENT   ce:cross-ref        ( %text.data; )* >
<!ATTLIST   ce:cross-ref
                %common-link.att;
                refid           IDREF               #REQUIRED>

<!ELEMENT   ce:cross-refs       ( %text.data; )* >
<!ATTLIST   ce:cross-refs
                %common-link.att;
                refid           IDREFS              #REQUIRED>

<!-- reference to objects in related documents -->

<!ELEMENT   ce:intra-ref        ( %text.data; )* >
<!ATTLIST   ce:intra-ref
                %common-link.att;
                xlink:type      (simple)            #FIXED  "simple"
                xlink:role      CDATA               #IMPLIED
                xlink:href      CDATA               #REQUIRED>

<!ELEMENT   ce:intra-refs       ( ce:intra-refs-text, ce:intra-ref-end+, ce:intra-refs-link )>
<!ATTLIST   ce:intra-refs
                %common-link.att;
                xlink:type      (extended)          #FIXED  "extended">
<!ELEMENT   ce:intra-refs-text  ( %text.data; )* >
<!ATTLIST   ce:intra-refs-text
                %common-link.att;
                xlink:type      (resource)          #FIXED  "resource"
                xlink:label     (intra-refs-start)  #FIXED  "intra-refs-start">
<!ELEMENT   ce:intra-ref-end    ( ce:intra-ref-title? )>
<!ATTLIST   ce:intra-ref-end
                xlink:type      (locator)           #FIXED  "locator"
                xlink:label     (intra-ref-end)     #FIXED  "intra-ref-end"
                xlink:role      CDATA               #IMPLIED
                xlink:href      CDATA               #REQUIRED>
<!ELEMENT   ce:intra-ref-title  ( %text.data; )* >
<!ATTLIST   ce:intra-ref-title
                xlink:type      (title)             #FIXED  "title">
<!ELEMENT   ce:intra-refs-link  EMPTY>
<!ATTLIST   ce:intra-refs-link
                xlink:type      (arc)               #FIXED  "arc"
                xlink:from      (intra-refs-start)  #FIXED  "intra-refs-start"
                xlink:to        (intra-ref-end)     #FIXED  "intra-ref-end">

<!-- reference to global external entity -->

<!ELEMENT   ce:inter-ref        ( %text.data; )* >
<!ATTLIST   ce:inter-ref
                %common-link.att;
                xlink:type      (simple)            #FIXED  "simple"
                xlink:role      CDATA               #IMPLIED
                xlink:href      CDATA               #REQUIRED
                versionurl      CDATA               #IMPLIED
                versiondate     CDATA               #IMPLIED>

<!ELEMENT   ce:inter-refs       ( ce:inter-refs-text?, ce:inter-ref-end+, ce:inter-refs-link )>
<!ATTLIST   ce:inter-refs
                %common-link.att;
                xlink:type      (extended)          #FIXED  "extended">
<!ELEMENT   ce:inter-refs-text  ( %text.data; )* >
<!ATTLIST   ce:inter-refs-text
                %common-link.att;
                xlink:type      (resource)          #FIXED  "resource"
                xlink:label     (inter-refs-start)  #FIXED  "inter-refs-start">
<!ELEMENT   ce:inter-ref-end    ( ce:inter-ref-title? )>
<!ATTLIST   ce:inter-ref-end
                xlink:type      (locator)           #FIXED  "locator"
                xlink:label     (inter-ref-end)     #FIXED  "inter-ref-end"
                xlink:role      CDATA               #IMPLIED
                xlink:href      CDATA               #REQUIRED
                versionurl      CDATA               #IMPLIED
                versiondate     CDATA               #IMPLIED>
<!ELEMENT   ce:inter-ref-title  ( %text.data; )* >
<!ATTLIST   ce:inter-ref-title
                xlink:type      (title)             #FIXED  "title">
<!ELEMENT   ce:inter-refs-link  EMPTY>
<!ATTLIST   ce:inter-refs-link
                xlink:type      (arc)               #FIXED  "arc"
                xlink:from      (inter-refs-start)  #FIXED  "inter-refs-start"
                xlink:to        (inter-ref-end)     #FIXED  "inter-ref-end">

<!-- list  -->

<!ELEMENT   ce:list             ( ce:label?, ce:section-title?, ce:list-item+ )>
<!ATTLIST   ce:list
                %common-optref.att;
                %common-role.att; >
<!ELEMENT   ce:list-item        ( ce:label?, ce:para+ )>
<!ATTLIST   ce:list-item
                %common-optref.att; >

<!-- definition list -->

<!ELEMENT   ce:def-list         ( ce:label?, ce:section-title?,
                                  ( ce:def-term, ce:def-description? )+ )>
<!ATTLIST   ce:def-list
                %common-optref.att;
                %common-role.att; >
<!ELEMENT   ce:def-term         ( %textref.data; )* >
<!ATTLIST   ce:def-term
                %common-optref-link.att; >
<!ELEMENT   ce:def-description  ( ce:para+ )>
<!ATTLIST   ce:def-description
                %common-optref-link.att; >

<!-- inline figure  -->

<!ELEMENT   ce:inline-figure    ( ce:link, ce:alt-text* )>
<!ATTLIST   ce:inline-figure
                baseline        NMTOKEN             "0.0">

<!-- chemistry -->

<!ELEMENT   ce:chem             ( %textfn.data; )* >

<!-- float and display containers -->

<!ELEMENT   ce:floats           ( ce:figure*, ce:table*, ce:textbox*, ce:e-component* )>
<!ELEMENT   ce:float-anchor     EMPTY>
<!ATTLIST   ce:float-anchor
                refid           IDREF               #REQUIRED>

<!ELEMENT   ce:display          ( ce:figure | ce:table | ce:textbox | ce:e-component | ce:formula )>

<!ELEMENT   ce:caption          ( ce:simple-para+ )>
<!ATTLIST   ce:caption
                %common-optref-link.att;
                %common-role.att;
                xml:lang        %iso639;            #IMPLIED>

<!ELEMENT   ce:alt-text ( %string.data; )>
<!ATTLIST   ce:alt-text
                %common-optref-link.att;
                %common-role.att;>

<!ELEMENT   ce:source           ( %note.data; )* >
<!ATTLIST   ce:source
                %common-optref-link.att;
                %common-role.att; >

<!-- formulas -->

<!ELEMENT   ce:formula          ( ce:label?, ( %math; | ce:chem | ce:link | ce:formula+ ))>
<!ATTLIST   ce:formula
                %common-optref-link.att; >

<!ELEMENT   ce:math             EMPTY>
<!ATTLIST   ce:math
                %common-reqaltimg.att; >

<!-- figure  -->

<!ELEMENT   ce:figure           ( ce:label?, ce:caption*, ce:alt-text*, ce:source?,
                                  ( %copyright; )?, ce:keywords*,
                                  ( ce:link | ce:figure )+ )>
<!ATTLIST   ce:figure
                %common-optref-link.att;
                %common-role.att; >

<!-- textboxes -->

<!ELEMENT   ce:textbox          ( ce:label?, ce:caption*, ce:alt-text*, ce:source?,
                                  ( %copyright; )?, ce:keywords*, ce:legend?,
                                  ce:textbox-head?, ce:textbox-body, ce:textbox-tail? )>
<!ATTLIST   ce:textbox
                %common-optref-link.att;
                %common-role.att; >

<!ELEMENT   ce:textbox-head     ( ce:title?, ce:subtitle?, (ce:alt-title, ce:alt-subtitle?)*,
                                  ce:author-group*, ce:intro? )>
<!ELEMENT   ce:textbox-body     ( ce:sections, ce:acknowledgment?, ce:appendices? )>
<!ELEMENT   ce:textbox-tail     ( ce:bibliography?, ce:further-reading?,
                                  ce:glossary?, ce:biography* )>

<!-- multi-media component -->

<!ELEMENT   ce:e-component      ( ce:label?, ce:caption*, ce:alt-text*, ce:source?,
                                  ( %copyright; )?, ce:keywords*,
                                  ( ( ce:link, ce:alt-e-component? ) | ce:e-component )+ )>
<!ATTLIST   ce:e-component
                %common-optref-link.att;
                %common-role.att; >
<!ELEMENT   ce:alt-e-component  ( ce:link | ( ce:caption+, ce:link? ) )>
<!ATTLIST   ce:alt-e-component
                %common-optref-link.att; >

<!-- text effects -->

<!ELEMENT   ce:bold             ( %richstring.data; )* >
<!ELEMENT   ce:italic           ( %richstring.data; )* >
<!ELEMENT   ce:sans-serif       ( %richstring.data; )* >
<!ELEMENT   ce:monospace        ( %richstring.data; )* >
<!ELEMENT   ce:small-caps       ( %richstring.data; )* >

<!ELEMENT   ce:underline        ( %richstring.data; )* >
<!ELEMENT   ce:cross-out        ( %richstring.data; )* >

<!ELEMENT   ce:sup              ( %richstring.data; )* >
<!ATTLIST   ce:sup
                loc             %loc;               "post">
<!ELEMENT   ce:inf              ( %richstring.data; )* >
<!ATTLIST   ce:inf
                loc             %loc;               "post">
<!ELEMENT   ce:hsp              EMPTY>
<!ATTLIST   ce:hsp
                sp              NMTOKEN             "1.0">
<!ELEMENT   ce:vsp              EMPTY>
<!ATTLIST   ce:vsp
                sp              NMTOKEN             "1.0">
<!ELEMENT   ce:br               EMPTY>

<!-- non-Unicode glyphs -->

<!ELEMENT   ce:glyph            EMPTY >
<!ATTLIST   ce:glyph
                name            %glyph-names;               #REQUIRED>

<!-- grant information -->

<!ELEMENT   ce:grant-sponsor    ( %text.data; )* >
<!ATTLIST   ce:grant-sponsor
                %common-optref-link.att;
                %common-role.att;
                xlink:type      (simple)            #FIXED  "simple"
                xlink:role      CDATA               #FIXED  "https://www.elsevier.com/xml/linking-roles/grant-sponsor"
                xlink:href      CDATA               #IMPLIED
                sponsor-id      CDATA               #IMPLIED>
<!ELEMENT   ce:grant-number     ( %text.data; )* >
<!ATTLIST   ce:grant-number
                %common-link.att;
                refid           IDREF               #REQUIRED>

<!-- examination -->

<!ELEMENT   ce:exam-reference      ( ce:inter-ref )>
<!ATTLIST   ce:exam-reference
                %common-view.att; >
<!ELEMENT   ce:exam-questions      ( ce:section-title?, %parsec; )>
<!ATTLIST   ce:exam-questions
                %common-optref-link.att;
                %common-role.att;
                %common-view.att; >
<!ELEMENT   ce:exam-answers        ( ce:section-title?, %parsec; )>
<!ATTLIST   ce:exam-answers
                %common-optref-link.att;
                %common-role.att;
                %common-view.att; >

<!-- MathML3, with namespace prefix mml -->

<!ENTITY % MATHML.prefixed "INCLUDE" >
<!ENTITY % MATHML.prefix   "mml" >

<!ENTITY % mtext.mdl       " %nondisplay.data; | %MATHML.prefix;:mglyph | %MATHML.prefix;:malignmark " >

<!ENTITY % MMLIDTYPE    "ID" >
<!ENTITY % MMLIDREFTYPE "IDREF" >

<!ENTITY % mathml-dtd
    PUBLIC "-//W3C//DTD MathML 3.0 Mod ES//EN"
    "mathml3-mod-ES.dtd">
%mathml-dtd;

<!-- Extended CALS table model -->

<!ELEMENT   ce:legend           ( ce:simple-para+ )>
<!ELEMENT   ce:table-footnote   ( ce:label, ce:note-para+ )>
<!ATTLIST   ce:table-footnote
                %common-reqref.att;
                %common-role.att; >

<!ENTITY % yesorno              "(0|1)" >
<!ELEMENT   tb:top-border                           EMPTY>
<!ATTLIST   tb:top-border
                type            %hline;             'bar'
                style           %style;             's'>
<!ELEMENT   tb:left-border                          EMPTY>
<!ATTLIST   tb:left-border
                type            %vline;             'vb'
                style           %style;             's'>
<!ELEMENT   tb:bottom-border                        EMPTY>
<!ATTLIST   tb:bottom-border
                type            %hline;             'bar'
                style           %style;             's'>
<!ELEMENT   tb:right-border                         EMPTY>
<!ATTLIST   tb:right-border
                type            %vline;             'vb'
                style           %style;             's'>
<!ELEMENT   tb:alignmark                            EMPTY >
<!ELEMENT   tb:colspec                              EMPTY >
<!ATTLIST   tb:colspec
                colnum          NMTOKEN             #IMPLIED
                colname         NMTOKEN             #IMPLIED
                colwidth        CDATA               #IMPLIED
                colsep          %yesorno;           #IMPLIED
                rowsep          %yesorno;           #IMPLIED
                align           (mark)              #FIXED  'mark' >

<!ENTITY % tbl.titles           "ce:label?, ce:caption*, ce:alt-text*, ce:source?,
                                 ( %copyright; )?,  ce:keywords*" >
<!ENTITY % tbl.back             "ce:legend?, ce:table-footnote*" >

<!ENTITY % tbl.table.name       "ce:table" >
<!ENTITY % tbl.table-titles.mdl "%tbl.titles;," >
<!ENTITY % tbl.table-back.mdl   ",%tbl.back;" >
<!ENTITY % tbl.table-main.mdl   "(tgroup | ce:link)+" >
<!ENTITY % tbl.table.mdl        "%tbl.table-titles.mdl; %tbl.table-main.mdl; %tbl.table-back.mdl;" >
<!ENTITY % tbl.table.att        '
                %common-optref-link.att;
                %common-role.att;
                xmlns           CDATA               #FIXED  %CALS.xmlns;
                xmlns:tb        CDATA               #FIXED  %ESTB.xmlns; '>
<!ENTITY % tbl.tgroup.mdl       "(colspec | tb:colspec)*, thead?, tbody">
<!ENTITY % tbl.tgroup.att       '
                %common-altimg.att; '>
<!ENTITY % tbl.entry.mdl        "(%cell.data;)*" >
<!ENTITY % tbl.entry.att        '
                %common-optref-link.att;
                %common-role.att;
                xmlns           CDATA               #FIXED  %ESCE.xmlns; '>
<!ENTITY % tbl.colspec.att      '
                %common-role.att; '>
<!ENTITY % tbl.row.att          '
                %common-optref-link.att;
                %common-role.att; '>

<!ENTITY % CALS-dtd
    PUBLIC "-//OASIS//DTD XML Exchange Table Model 19990315//EN"
    "soextblx.dtd">
%CALS-dtd;