Some citations are complicated by the fact that they do not provide the full
citation information for each cited reference. For example, some journals identify
successive bibliographic references by the same author or involving the same journal by
omitting the duplicated portion of the reference and inserting a vertical rule, the word
“Ibid”, the word “Id.”, etc. Other publishers routinely
omit the title of a cited journal article to save space. While best practice is to tag
all citations completely, archives or publishers may choose to tag an abbreviated
citation exactly as it was displayed.
If it is important for an archive or publisher to make each citation accessible for
citation matching services, incomplete references should be enhanced by tagging the
missing information based on the preceding reference. At the discretion of the archive,
the word “Ibid” or “Id.” may also be retained as part of
the textual content.
As an example, here is a citation that mixes multiple works by a single
author:
Holmes, S. J. (1) Phototaxis in the amphipoda. Am. Jour.
Physiol., 5, 211, 1901; (2) The reactions of Ranatra to
light. Jour. Comp. Neur. Psych., 15, 305, 1905.
To preserve the exact order and punctuation of these citations, each publisher or
archive must decide whether the semicolon and space between the citations is part of the
first citation or the second. Here is the double-citation reference tagged as a
mixed-style citation, with the punctuation added to the end of the first
citation:
<ref id="ref1" content-type="double-author">
<mixed-citation publication-type="journal">
<string-name>
<surname>Holmes</surname>, <given-names>S.J.</given-names>
</string-name> <label>(1)</label> <article-title>Phototaxis
in the amphipoda</article-title>. <source>Am. Jour.
Physiol.</source>, <volume>5</volume>, <issue>211
</issue>, <year>1901</year>; </mixed-citation>
<mixed-citation><label>(2)</label> <article-title>The
reactions of Ranatra to light</article-title>. <source>Journ.
Comp. Neur. Physch.</source>, <volume>15</volume>,
<issue>305</issue>, <year>1905</year>.
</mixed-citation>
</ref>
If completeness of citations for reference matching is more important than
preserving the original word order and exact punctuation, information that is only
displayed in one citation should be tagged in both. Because display is less important
than completeness, the label can be moved to the beginning of the citation. Here is the
same citation tagged as an element-style citation and incorporating the changes just
mentioned:
<ref id="ref1" content-type="double-author">
<element-citation publication-type="journal">
<label>(1)</label>
<name><surname>Holmes</surname><given-names>S.J.</given-names></name>
<article-title>Phototaxis in the amphipoda</article-title>
<source>Am. Jour. Physiol.</source>
<volume>5</volume><issue>211</issue><year>1901</year>
</element-citation>
<element-citation>
<label>(2)</label>
<name><surname>Holmes</surname><given-names>S.J.</given-names></name>
<article-title>The reactions of Ranatra to light</article-title>
<source>Journ. Comp, Neur. Physch.</source>
<volume>15</volume><issue>305</issue><year>1905</year>
</element-citation>
</ref>