<!– ============================================================= –> <!– MODULE: Link Element Classes –> <!– VERSION: 2.3 –> <!– DATE: February 2007 –> <!– –> <!– ============================================================= –>

<!– ============================================================= –> <!– PUBLIC DOCUMENT TYPE DEFINITION –> <!– TYPICAL INVOCATION –> <!– “-//NLM//DTD Archiving and Interchange DTD Suite Link Class Elements v2.3 20070202//EN”

Delivered as file "link.ent"                                  -->

<!– ============================================================= –>

<!– ============================================================= –> <!– SYSTEM: Archiving and Interchange DTD Suite –> <!– –> <!– PURPOSE: Names all elements in the link class. These are –> <!– elements that are links (internal or external) –> <!– by definition, such as URLs <uri> and –> <!– Cross(X)-references <xref>. –> <!– –> <!– CONTAINS: 1) Default definitions of the link classes –> <!– 2) Default definitions for attribute values –> <!– 3) Default definitions for attribute lists –> <!– 4) Models for the link class elements, first –> <!– internal links then external links –> <!– (alphabetically) –> <!– –> <!– (Note: Links make their links using the XLink –> <!– global attributes. Many elements besides –> <!– explicit links may be made into links using –> <!– these attributes. Such elements are defined in –> <!– the module appropriate to their use and are not –> <!– listed here.) –> <!– –> <!– 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 –> <!– important contributions. –> <!– –> <!– ============================================================= –>

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

=============================================================

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

    =============================================================
    Version 2.3                       (DAL/BTU) v2.3 (2007-02-02)

    Enhancement Release (2.3) following the Working Group meetings 
    of Oct-Nov/2006-Jan/2007. No backward-incompatible changes.
    Archiving loosened even more. New structures for all the DTDs. 

14. NEW TYPE ATTRIBUTES - Added "content-type" attribute to the
    following elements
    - inline-supplementary-material  

13. NEW PARAMETER ENTITIES - Added parameter entities for the
    attribute lists of:
    - target

12. Updated public identifier to "v2.3 20070202//EN"          

    =============================================================
    Version 2.1                       (DAL/BTU) v2.1 (2005-06-30)

    Changed to MathML 2.0 and MathML 2.0 Character Sets
    Added new material requested by NCBI   

11. Minor, non-functional changes to wording in comments as part 
    of 2.1 release.

10. Updated public identifier to "v2.3 20070202" 

    =============================================================
    Version 2.0                       (DAL/BTU) v2.0 (2004-08-30)

    Major requirement changes led to the new release, producing
    DTD version "2.0":
      a) The splitting of the Archival and Interchange Tag Set 
         DTDs into three DTDs from two: an authoring DTD, an
         archive regularization and interchange DTD (the
         current Blue Publishing DTD), and a preservationist 
         archive DTD (the current Green Archiving and Interchange 
         DTD).
      b) AIT Working Group suggestions from the June 04 meeting 
         and June/July 2004 followup discussions
      c) Suite remodularization to meet new (and newly articulated)
         modularization requirements
      d) New or renamed classes and mixes to make modifications
         easier and more consistent

 9. COMPLETE MODELS WHEN OVER-RIDING A MODEL 
    (for all Parameter Entities suffixed "-model")
    ### Customization Alert ###
    Made all the model over-rides consistent. Some included
    the outer parentheses, some did not. They all do now,
    -  %fn-model; 

 8. DEFAULT CLASSES - Were moved from this module to 
    %default-classes.ent;

 7. FOOTNOTE
       - Made model into a Parameter Entity
       - Added optional <label> to the beginning of the model,
         before the paragraphs

 6. To correct potential classing problems, used the following
    new Parameter Entities:
       - %just-para.class; used in <fn> (%fn-model; uses 
         %just-para.class;)

 5. Updated public identifier to "v2.3 20070202"

    =============================================================
    Version 1.1                         (TRG/BTU) v1.1 (2003-11-01)

 4. Added "alternate-form-of", "content-type", and ID attributes 
    to <inline-supplementary-material> (by modifying 
    %inline-supplementary-material-atts;)
    Rationale: To provide parallelism between attributes for 
    <supplementary-material> and <inline-supplementary-material>

 3. Added "mimetype" and "mime-subtype" attributes to 
    <inline-supplementary-material> (as part of adding these 
    attributes to all graphic and multi-media elements)

 2. Added ID attribute information to <xref> (by modifying
    parameter entity %xref-atts;)
    Rationale: Provide unique identifier so <xref>
    element can be linked to (creating two-way link). 

 1. Added an optional "target-type" attribute to element 
    <target>.  Rationale: To identify the reason for this target.
                                                                  -->

<!– ============================================================= –> <!– PARAMETER ENTITY DEPENDENCIES

Requires the following parameter entities
be defined before calling this module, 
usually accomplished in the Customization
Module for the specific DTD:
  %access.class;
  %emphasis.class;
  %link-elements;
  %might-link-atts;
  %subsup.class;
                                           -->

<!– ============================================================= –> <!– DEFAULTS FOR ATTRIBUTE VALUES –> <!– ============================================================= –>

<!– DEFAULT TYPE OF CROSS(X)-REFERENCE –> <!– Used to say to what the reference is pointing.

May be used for type-specific processing or
validation. Values are, for example:
Affiliation "aff", Figure "fig", and
Bibliographic ref (to a Citation <citation> or
to a Reference Item <ref>) "bibr"          -->

<!ENTITY % ref-types “aff | app | author-notes | bibr |

boxed-text | chem | contrib | corresp | 
disp-formula | fig | fn | kwd | list | 
plate | scheme | sec | statement | 
supplementary-material | 
table | table-fn | 
other"                                      >

<!– ============================================================= –> <!– DEFAULTS FOR ATTRIBUTE LISTS –> <!– ============================================================= –>

<!– FOOTNOTE ATTRIBUTES –> <!– Attribute list for Footnote element –> <!ENTITY % fn-atts

"id         ID                                #IMPLIED  
 symbol     CDATA                             #IMPLIED 
 fn-type    CDATA                             #IMPLIED  
 xml:lang   NMTOKEN                           #IMPLIED" >

<!– INLINE SUPPLEMENTARY MATERIAL –> <!– Attribute list for inline supplementary

material                                   -->

<!ENTITY % inline-supplementary-material-atts

"alternate-form-of
           IDREF                             #IMPLIED
 content-type
           CDATA                             #IMPLIED
 id        ID                                #IMPLIED
 %might-link-atts;                                    
 mimetype  CDATA                             #IMPLIED 
 mime-subtype
           CDATA                             #IMPLIED"  >

<!– TARGET ATTRIBUTES –> <!– Attribute list for <target> element –> <!ENTITY % target-atts

"id        ID                                #IMPLIED
 target-type
           CDATA                             #REQUIRED" >

<!– X(CROSS) REFERENCE ATTRIBUTES –> <!– Attribute list for cross references –> <!ENTITY % xref-atts

"id         ID                               #IMPLIED
 ref-type   (%ref-types;)                    #IMPLIED 
 rid        IDREFS                           #IMPLIED"  >

<!– ============================================================= –> <!– INTERNAL LINKS –> <!– ============================================================= –>

<!– FOOTNOTE MODEL –> <!– Content model for Footnote <fn> –> <!ENTITY % fn-model “((%label.class;)?, (%just-para.class;)+ )” >

<!– FOOTNOTE –> <!– Additional information concerning material in

a particular location in the text. This
material is not considered to be part of the 
body of the text, but in addition to or a 
commentary on the body. Such material may be 
displayed at the bottom of a printed page, 
onscreen in a separate pop-up window, or in a
list at the end of an article.
Remarks: A reference (pointer) to a
Footnote <fn> is made with the X(Cross)
Reference element.
The language attribute may be used to note
a footnote that is not in the same language
as the original document, for example, a
Latin or Greek footnote for a document in 
English.                                   -->

<!ELEMENT fn %fn-model; > <!– id Unique identifier for the element. A cross-

            reference will point to this ID.
 symbol     If the symbol that was used in the original
            display to identify the specific footnote
            is to be preserved, this is the attribute
            where it may be stored. One might store the
            symbol to disambiguate mistagged cases, for
            example, in which the author has stated
            "see footnote b" or "see footnote 14"  in
            the text but the mention of the footnote has 
            not been tagged as a cross references.
 fn-type    Type of footnote, for those footnotes that
            point to a particular type of information 
            and that type is known, this attribute is
            intended as a way to preserve that
            knowledge.  For example, some footnotes
            point to or are used for the purpose of
            recording:
              abbr    Abbreviations
              com     Communicated-by information
              con     Contributed-by information
              conflict
                      Conflict of interest statements
              equal   Contributed to the creation of
                      the document equally
              corresp For use when the corresponding
                      author information is not 
                      identified separately, but is 
                      merely a footnote
              current-aff
                      Contributor's current affiliation
              deceased
                      Person has died since article was
                      written
              edited-by
                      Contributor has the role of an
                      editor
              financial-disclosure
                      Statement of funding or denial
                      of funds received in support of
                      the research on which this article
                      is based
              on-leave
                      Contributor is on sabbatical or
                      other leave of absence
              participating-researchers
                      Contributor was a researcher for
                      this article
              present-address
                      Contributor's current address
              presented-at
                      Conference, colloquium, or other
                      occasion at which this paper
                      was presented
              presented-by
                      Contributor who presented this
                      material
              previously-at
                      Contributor's previous location
                      or affiliation
              reprint Method or place to obtain reprints,
                      typically the name and address of
                      a person from whom reprints can be
                      requested
              study-group-members
                      Contributor was a member of the
                      study group for this research
              supplementary-material
                      Points to or describes
                      supplementary material for this
                      article
              supported-by
                      The research upon which this
                      article is based was supported by
              other    Not in the above list of
                       footnote types
xml:lang   The language in which the value of the
            element is expressed.  Recommended best 
            practice is to use values as defined in
            RFC 1766, typically 2-letter language
            codes such as "FR" (French), "EN" (English),
            and "DE" (German). These values are NOT
            case sensitive, so "EN" = "en". The values
            may include hyphenated differentiations such 
            as "EN-AU" (Australian English) and "EN-US"
            (United States English).                   -->

<!ATTLIST fn

%fn-atts;                                               >

<!– TARGET ELEMENTS –> <!– The elements that can be included along with

data characters inside the content model of
a <target>  
Design Note: All inline mixes begin with an
OR bar, but since %link-elements; is an inline
mix, the OR bar is already there.          -->

<!ENTITY % target-elements

"%link-elements;"                            >

<!– TARGET OF AN INTERNAL LINK –> <!– May be placed anywhere within textual

material such as a paragraph to provide a
location (anchor) to which a cross reference
can point                                  -->

<!ELEMENT target (#PCDATA %target-elements;)* > <!– id Unique identifier so the element may be

           referenced
target-type
           Indicates the kind of <target> that has 
           been created, i.e., describes the reason 
           why some portion of text has been 
           designated for cross-references purposes   -->

<!ATTLIST target

%target-atts;                                           >

<!– X(CROSS) REFERENCE ELEMENTS –> <!– The elements that can be included along with

data characters inside the content model of
an <xref>  
Design Note: All inline mixes begin with an
OR bar, but since %link-elements; is an inline
mix, the OR bar is already there.          -->

<!ENTITY % xref-elements

"%link-elements;"                            >

<!– X(CROSS) REFERENCE –> <!– Used for any kind of internal article

referencing. The content of the reference 
(if present) will be displayed as the link.
This element may be used to point to any 
element that takes an "id" attribute.
The "ref-type" attribute may be used to name
the element or type of object to which the 
<xref> is pointing.                        -->

<!ELEMENT xref (#PCDATA %xref-elements;)* > <!– id Unique identifier so the element may be

           referenced (creating two-way link)
ref-types  Used to say to what the reference is pointing.
           May be used for type-specific processing or
           validation.  
           Values are:
             aff       Affiliation
             app       Appendix
             author-note
                       Author Note
             bibr      Bibliographic ref (to 
                       a Citation <citation>
                       or to a Reference 
                       Item <ref>) 
             boxed-text
                       Textbox or sidebar  
             chem      Chemical Structure 
                       Wrapper or Chemical
                       Structure
             contrib   Contributor
             corresp   Corresponding Author
             disp-formula        
                       Display Formula 
             fig       Figure or fig-group
             kwd       Keyword
             fn        Footnote
             list      List 
             plate     Plate
             scheme    Scheme
             sec       Section
             statement Statement
             supplementary-material  
                       Supplementary Information
             table     Table Group or Table Wrapper              
             table-fn  Table foot Note
                       A <fn> that is found within a
                       <table-wrap> element and that
                       should be displayed with the 
                       table rather than, for example, 
                       at the bottom of the page or 
                       in a window that does not contain
                       the table.
             other     Not listed above               
rid        Points to the identifier of a bibliographic
           reference, boxed-text, figure, footnote, 
           table, etc. (creating a link)              -->

<!ATTLIST xref

%xref-atts;                                             >

<!– ============================================================= –> <!– EXTERNAL LINKS –> <!– ============================================================= –>

<!– INLINE SUPPLEMENTARY MATERIAL ELEMENTS –> <!– Elements for use in the

<inline-supplementary-material> element    -->

<!ENTITY % inline-supplementary-material-elements

"| %access.class; | %address-link.class; | 
 %emphasis.class; | %subsup.class;"          >

<!– INLINE SUPPLEMENTARY MATERIAL –> <!– An in-text link to an external file that

provides supplementary information for
the document, for example, an audio clip   -->

<!ELEMENT inline-supplementary-material

(#PCDATA 
 %inline-supplementary-material-elements;)*  >

<!– alternate-form-of

           Where multiple formats of an item (e.g., 
           graphic file, media object, chemical 
           structure) are available, this attribute 
           indicates that a format is a secondary 
           one and provides a link to the primary 
           format, so that only one format of an
           item is displayed.
content-type   
           Identification of the subject, type of
           content, or reason that this word or phrase
           is considered semantically special, as a 
           means of preserving the semantic intent of 
           the original tagging.                      
id         Unique identifier so the element may be
           referenced                              
mimetype   The mime type of the supplementary material
           Authoring Note: This attribute might be
           required when creating new articles.       
mime-subtype   
           The subtype of the supplementary material 
xlink:href Provides an address or identifier of the
           object to which the link points, for
           example a URI or a filename                -->

<!ATTLIST inline-supplementary-material

%inline-supplementary-material-atts;                    >

<!– ================== End Link Class Module ==================== –>