coref — A cross reference to a co
The coref plays a role for callouts that is analagous
to the role of footnoteref for footnotes.
Use one co and one or more
coref elements when you want to indicate that the
same callout should appear in several places.
A coref is not a cross-reference to a callout
(use xref for that), rather, it is an indication that the
callout appears semantically in more than one place.
These elements contain coref: bridgehead, citation, citetitle, classsynopsisinfo, emphasis (db.emphasis), entry, firstterm, foreignphrase, funcsynopsisinfo, glosssee, glossseealso, glossterm, html:button, html:label, html:legend, link, literallayout, member, olink, orgdiv, para, phrase (db.phrase), primary, primaryie, programlisting, quote, refdescriptor, refentrytitle, refname, refpurpose, screen, secondary, secondaryie, see, seealso, seealsoie, seeie, seg, segtitle, simpara, subtitle, synopsis, td, term, termdef, tertiary, tertiaryie, th, title, titleabbrev, tocentry.