<!-- ============================================================= -->
<!--  MODULE:    Formatting Element Classes                        -->
<!--  VERSION:   3.0                                               -->
<!--  DATE:      Feb 2008                                          -->
<!--                                                               -->
<!-- ============================================================= -->

<!-- ============================================================= -->
<!--                    PUBLIC DOCUMENT TYPE DEFINITION            -->
<!--                        TYPICAL INVOCATION                     -->
<!--
 "-//NLM//DTD Archiving and Interchange DTD Suite Formatting Element Classes v3.0 20080202//EN"
  Delivered as file "format3.ent"                                  -->
<!-- ============================================================= -->

<!-- ============================================================= -->
<!-- SYSTEM:     Archiving and Interchange DTD Suite               -->
<!--                                                               -->
<!--                                                               -->
<!-- PURPOSE:    Elements concerned with rendition of output, for  -->
<!--             example printing on a page or display on a screen -->
<!--                                                               -->
<!-- CONTAINS:   1) Default definitions of format classes          -->
<!--             2) Appearance class elements                      -->
<!--             3) Break class elements                           -->
<!--             4) Typographic emphasis elements                  -->
<!--             5) Advanced overline and underline elements       -->
<!--                                                               -->
<!-- CREATED FOR:                                                  -->
<!--             Digital archives and publishers who wish to       -->
<!--             create a custom XML DTD for original markup of    -->
<!--             journal literature, books, and related material,  -->
<!--             or for archiving and transferring such material   -->
<!--             between archives.                                 -->
<!--                                                               -->
<!--             This DTD is in the public domain. An organization -->
<!--             that wishes to create its own DTD from the suite  -->
<!--             may do so without permission from NLM.            -->
<!--                                                               -->
<!--             The suite has been set up to be extended using a  -->
<!--             new DTD file and a new DTD-specific customization -->
<!--             module to redefine the many Parameter Entities.   -->
<!--             Do not modify the suite directly or redistribute  -->
<!--             modified versions of the suite.                   -->
<!--                                                               -->
<!--             In the interest of maintaining consistency and    -->
<!--             clarity for potential users, NLM requests:        -->
<!--                                                               -->
<!--             1. If you create a DTD from the Archiving and     -->
<!--                Interchange DTD Suite and intend to stay       -->
<!--                compatible with the suite, then please include -->
<!--                the following statement as a comment in all of -->
<!--                your DTD modules:                              -->
<!--                   "Created from, and fully compatible with,   -->
<!--                    the Archiving and Interchange DTD Suite."  -->
<!--                                                               -->
<!--             2. If you alter one or more modules of the suite, -->
<!--                then please rename your version and all its    -->
<!--                modules to avoid any confusion with the        -->
<!--                original suite. Also, please include the       -->
<!--                following statement as a comment in all your   -->
<!--                DTD modules:                                   -->
<!--                   "Based in part on, but not fully compatible -->
<!--                    with, the Archiving and Interchange DTD    --> 
<!--                    Suite."                                    -->
<!--                                                               -->
<!--             Suggestions for refinements and enhancements to   -->
<!--             the DTD suite should be sent in email to:         -->
<!--                 archive-dtd@ncbi.nlm.nih.gov                  -->
<!--                                                               -->
<!-- ORIGINAL CREATION DATE:                                       -->
<!--             December 2002                                     -->
<!--                                                               -->
<!-- CREATED BY: Jeff Beck       (NCBI)                            -->
<!--             Deborah Lapeyre (Mulberry Technologies, Inc.)     -->
<!--             Bruce Rosenblum (Inera Inc.)                      -->
<!--                                                               -->
<!--             NLM thanks the Harvard University Libraries, both -->
<!--             for proposing that a draft archiving NLM DTD for  --> 
<!--             life sciences journals be extended to accommodate -->
<!--             journals in all disciplines and for sponsoring    -->
<!--             Bruce Rosenblum's collaboration with other DTD    -->
<!--             authors in completing Version 1.0. The Andrew W.  --> 
<!--             Mellon Foundation provided support for these      --> 
<!--                                                               -->
<!--             Suggestions for refinements and enhancements to   -->
<!--             the DTD suite should be sent in email to:         -->
<!--                 archive-dtd@ncbi.nlm.nih.gov                  -->
<!--             important contributions.                          -->
<!--                                                               -->
<!-- ============================================================= -->


<!-- ============================================================= -->
<!--                    DTD VERSION/CHANGE HISTORY                 -->
<!-- ============================================================= -->
<!--
     =============================================================

Version  Reason/Occasion                   (who) vx.x (yyyy-mm-dd)

     =============================================================
     Version 3.0                       (DAL/BTU) v3.0 (2007-10-31)
     
     Version 3.0 is the first non-backward-compatible release.
     In addition to the usual incremental changes, some
     elements and attributes have been renamed and/or remodeled
     to better meet user needs and to increase tag set consistency.
     All module change histories are available through the Tag Suite 
     web site at http://dtd.nlm.nih.gov. 

     Details on version 3.0 are available at 
           http://dtd.nlm.nih.gov/3.0.
  
  1. Updated public identifier to "v3.0 20080202//EN"              -->


<!-- ============================================================= -->
<!--                    PARAMETER ENTITIES FOR ATTRIBUTE LISTS     -->
<!-- ============================================================= -->


<!--                    UNDERLINE ATTRIBUTES                       -->
<!--                    Attributes for the <underline> element     -->
<!ENTITY % underline-atts 
            "underline-style   
                        CDATA                             #IMPLIED"  >


<!-- ============================================================= -->
<!--                    APPEARANCE CLASS ELEMENTS                  -->
<!-- ============================================================= -->


<!--                    HORIZONTAL RULE                            -->
<!--                    Defined to allow the user to specify an
                        explicit (non machine-generated) rule.
                        Details at: 
                        http://dtd.nlm.nih.gov/archiving/tag-library/3.0/index.html?elem=hr
                        http://dtd.nlm.nih.gov/publishing/tag-library/3.0/index.html?elem=hr
                        http://dtd.nlm.nih.gov/articleauthoring/tag-library/3.0/index.html?elem=hr
                        http://dtd.nlm.nih.gov/book/tag-library/3.0/index.html?elem=hr
                                                                   -->
<!ELEMENT  hr           EMPTY                                        >


<!-- ============================================================= -->
<!--                    BREAK CLASS ELEMENTS                       -->
<!-- ============================================================= -->


<!--                    LINE BREAK                                 -->
<!--                    Defined to allow the user to specify an
                        explicit (non machine-generated) linebreak.
                        Details at: 
                        http://dtd.nlm.nih.gov/archiving/tag-library/3.0/index.html?elem=break
                        http://dtd.nlm.nih.gov/publishing/tag-library/3.0/index.html?elem=break
                        http://dtd.nlm.nih.gov/articleauthoring/tag-library/3.0/index.html?elem=break
                        http://dtd.nlm.nih.gov/book/tag-library/3.0/index.html?elem=break
                                                                   -->
<!ELEMENT  break        EMPTY                                        >


<!-- ============================================================= -->
<!--                    EMPHASIS/RENDITION CLASS ELEMENTS          -->
<!-- ============================================================= -->


<!--                    BOLD                                       -->
<!--                    Used to mark text that should appear in bold 
                        face type for print or display 
                        Details at: 
                        http://dtd.nlm.nih.gov/archiving/tag-library/3.0/index.html?elem=bold
                        http://dtd.nlm.nih.gov/publishing/tag-library/3.0/index.html?elem=bold
                        http://dtd.nlm.nih.gov/articleauthoring/tag-library/3.0/index.html?elem=bold
                        http://dtd.nlm.nih.gov/book/tag-library/3.0/index.html?elem=bold
                                                                   -->
<!ELEMENT  bold         (#PCDATA %emphasized-text;)*                 >


<!--                    ITALIC                                     -->
<!--                    Used to mark text that should appear in 
                        italic type on output. 
                        Details at: 
                        http://dtd.nlm.nih.gov/archiving/tag-library/3.0/index.html?elem=italic
                        http://dtd.nlm.nih.gov/publishing/tag-library/3.0/index.html?elem=italic
                        http://dtd.nlm.nih.gov/articleauthoring/tag-library/3.0/index.html?elem=italic
                        http://dtd.nlm.nih.gov/book/tag-library/3.0/index.html?elem=italic
                                                                   -->
<!ELEMENT  italic       (#PCDATA %emphasized-text;)*                 >


<!--                    MONOSPACE TEXT (TYPEWRITER TEXT)           -->
<!--                    Used to mark text that should appear in 
                        a non-proportional font, such as courier
                        for display or print.  This is common for
                        computer code examples, man-machine
                        dialogues, etc.
                        Details at: 
                        http://dtd.nlm.nih.gov/archiving/tag-library/3.0/index.html?elem=monospace
                        http://dtd.nlm.nih.gov/publishing/tag-library/3.0/index.html?elem=monospace
                        http://dtd.nlm.nih.gov/articleauthoring/tag-library/3.0/index.html?elem=monospace
                        http://dtd.nlm.nih.gov/book/tag-library/3.0/index.html?elem=monospace
                                                                   -->
<!ELEMENT  monospace    (#PCDATA %emphasized-text;)*                 >


<!--                    ROMAN                                      -->
<!--                    Used to mark text that should remain in 
                        roman script no matter what style the
                        surrounding text takes on.
                        Details at: 
                        http://dtd.nlm.nih.gov/archiving/tag-library/3.0/index.html?elem=roman
                        http://dtd.nlm.nih.gov/publishing/tag-library/3.0/index.html?elem=roman
                        http://dtd.nlm.nih.gov/articleauthoring/tag-library/3.0/index.html?elem=roman
                        http://dtd.nlm.nih.gov/book/tag-library/3.0/index.html?elem=roman
                                                                   -->
<!ELEMENT  roman        (#PCDATA %emphasized-text;)*                 >



<!--                    SANS SERIF                                 -->
<!--                    Used to mark text that should appear in a 
                        special sans-serif font, typically used in
                        math or chemistry  
                        Details at: 
                        http://dtd.nlm.nih.gov/archiving/tag-library/3.0/index.html?elem=sans-serif
                        http://dtd.nlm.nih.gov/publishing/tag-library/3.0/index.html?elem=sans-serif
                        http://dtd.nlm.nih.gov/book/tag-library/3.0/index.html?elem=sans-serif
                                                                   -->
<!ELEMENT  sans-serif   (#PCDATA %emphasized-text;)*                 >


<!--                    SMALL CAPS                                 -->
<!--                    Used to mark text that should appear in a 
                        font which creates smaller capital letters
                        on output. 
                        Details at: 
                        http://dtd.nlm.nih.gov/archiving/tag-library/3.0/index.html?elem=sc
                        http://dtd.nlm.nih.gov/publishing/tag-library/3.0/index.html?elem=sc
                        http://dtd.nlm.nih.gov/articleauthoring/tag-library/3.0/index.html?elem=sc
                        http://dtd.nlm.nih.gov/book/tag-library/3.0/index.html?elem=sc
                                                                   -->
<!ELEMENT  sc           (#PCDATA %emphasized-text;)*                 >


<!--                    OVERLINE                                   -->
<!--                    Used to mark text that should appear with a 
                        horizontal line above each character in
                        display or print. There is no PE for
                        override because this was added to handle
                        a specific publisher tag set and should not 
                        grow beyond what they need. 
                        Details at: 
                        http://dtd.nlm.nih.gov/archiving/tag-library/3.0/index.html?elem=overline
                        http://dtd.nlm.nih.gov/publishing/tag-library/3.0/index.html?elem=overline
                        http://dtd.nlm.nih.gov/articleauthoring/tag-library/3.0/index.html?elem=overline
                        http://dtd.nlm.nih.gov/book/tag-library/3.0/index.html?elem=overline
                                                                   -->
<!ELEMENT  overline     (#PCDATA %emphasized-text;)*                 >


<!--                    STRIKE THROUGH                             -->
<!--                    Used to mark text that should appear with 
                        a line through it so as to appear "struck out" 
                        on display or print  
                        Details at: 
                        http://dtd.nlm.nih.gov/archiving/tag-library/3.0/index.html?elem=strike
                        http://dtd.nlm.nih.gov/publishing/tag-library/3.0/index.html?elem=strike
                        http://dtd.nlm.nih.gov/articleauthoring/tag-library/3.0/index.html?elem=strike
                        http://dtd.nlm.nih.gov/book/tag-library/3.0/index.html?elem=strike
                                                                   -->
<!ELEMENT  strike       (#PCDATA %emphasized-text;)*                 >


<!--                    SUBSCRIPT                                  -->
<!--                    A number or expression that is set lower
                        than the baseline and slightly smaller,
                        to act as an inferior or subscript    
                        Details at: 
                        http://dtd.nlm.nih.gov/archiving/tag-library/3.0/index.html?elem=sub
                        http://dtd.nlm.nih.gov/publishing/tag-library/3.0/index.html?elem=sub
                        http://dtd.nlm.nih.gov/articleauthoring/tag-library/3.0/index.html?elem=sub
                        http://dtd.nlm.nih.gov/book/tag-library/3.0/index.html?elem=sub
                                                                   -->
<!ELEMENT  sub          (#PCDATA %emphasized-text;)*                 >
<!ATTLIST  sub 
             arrange    (stack | stagger)                  #IMPLIED  >


<!--                    SUPERSCRIPT                                -->
<!--                    A number or expression that is set higher
                        than the baseline and slightly smaller,
                        to act as a superior or superscript 
                        Details at: 
                        http://dtd.nlm.nih.gov/archiving/tag-library/3.0/index.html?elem=sup
                        http://dtd.nlm.nih.gov/publishing/tag-library/3.0/index.html?elem=sup
                        http://dtd.nlm.nih.gov/articleauthoring/tag-library/3.0/index.html?elem=sup
                        http://dtd.nlm.nih.gov/book/tag-library/3.0/index.html?elem=sup
                                                                   -->
<!ELEMENT  sup          (#PCDATA %emphasized-text;)*                 >
<!ATTLIST  sup 
             arrange    (stack | stagger)                  #IMPLIED  >


<!--                    UNDERLINE                                  -->
<!--                    Details at: 
                        http://dtd.nlm.nih.gov/archiving/tag-library/3.0/index.html?elem=underline
                        http://dtd.nlm.nih.gov/publishing/tag-library/3.0/index.html?elem=underline
                        http://dtd.nlm.nih.gov/articleauthoring/tag-library/3.0/index.html?elem=underline
                        http://dtd.nlm.nih.gov/book/tag-library/3.0/index.html?elem=underline
                                                                   -->
<!ELEMENT  underline    (#PCDATA %emphasized-text;)*                 >
<!ATTLIST  underline 
             %underline-atts;                                        >


<!-- ============================================================= -->
<!--                    ADVANCED UNDERLINE AND OVERLINE ELEMENTS
                        (From the Elsevier DTD, used mostly within    
                        mathematics, when ordinary MathML underline   
                        and overline functions are inadequate. The
                        elements act as milestone tags marking the
                        start and end of over or underlining that
                        may extend across element boundaries.)     -->
<!-- ============================================================= -->


<!--                    OVERLINE START                             -->
<!--                    The start of a milestone-created overline, the
                        end of ornament will be marked by an
                        Overline End element.
                        Details at: 
                        http://dtd.nlm.nih.gov/archiving/tag-library/3.0/index.html?elem=overline-start
                        http://dtd.nlm.nih.gov/book/tag-library/3.0/index.html?elem=overline-start
                                                                   -->
<!ELEMENT  overline-start     
                        EMPTY                                        >
<!ATTLIST  overline-start
             id         ID                                 #REQUIRED >


<!--                    OVERLINE END                               -->
<!--                    The end of a milestone-created overline, the
                        start of ornament will be marked by an
                        Overline Start element.
                        Details at: 
                        http://dtd.nlm.nih.gov/archiving/tag-library/3.0/index.html?elem=overline-end
                        http://dtd.nlm.nih.gov/book/tag-library/3.0/index.html?elem=overline-end
                                                                   -->
<!ELEMENT  overline-end EMPTY                                        >
<!ATTLIST  overline-end
             rid        IDREF                              #REQUIRED >


<!--                    UNDERLINE START                            -->
<!--                    The start of a milestone-created underline,
                        the end of ornament will be marked by an
                        Underline End element
                        Details at: 
                        http://dtd.nlm.nih.gov/archiving/tag-library/3.0/index.html?elem=underline-start
                        http://dtd.nlm.nih.gov/book/tag-library/3.0/index.html?elem=underline-start
                                                                   -->
<!ELEMENT  underline-start      
                        EMPTY                                        >
<!ATTLIST  underline-start
             id         ID                                 #REQUIRED >


<!--                    UNDERLINE END                              -->
<!--                    The end of a milestone-created underline, the
                        start of ornament will be marked by an
                        Underline Start element. 
                        Details at: 
                        http://dtd.nlm.nih.gov/archiving/tag-library/3.0/index.html?elem=underline-end
                        http://dtd.nlm.nih.gov/book/tag-library/3.0/index.html?elem=underline-end
                                                                   -->
<!ELEMENT  underline-end        
                        EMPTY                                         >
<!ATTLIST  underline-end
             rid        IDREF                               #REQUIRED >


<!-- ================== End Format Class Module =================== -->
