The <biblioref> element is an inline reference to a <biblioentry> or <bibliomixed> entry.
This element can be used mostly unchanged, however, I suggest the following interpretation for the attributes that define a location within a resource, and I recommend adding stylesheet parameters to allow <biblioref> to create an entry that includes both a title and a reference to the biblioentry.
unitsDefines the units (pages, sections, etc.) that begin and end refer to.
Units has the following values:
Page or pages.
Whether it should be plural or singular can be determined by looking at begin and end.
Section or sections.
Whether it should be plural or singular can be determined by looking at begin and end.
Volume or volumes.
Whether it should be plural or singular can be determined by looking at begin and end.
textText that does not match one of the keywords above is used verbatim.
emptyShow begin and end if present, but show nothing for units.
beginShould be a number (Arabic or Roman).
If the location is a single page, use begin and omit end.
If a text description for the location is needed, put the text into units (e.g., units="Preface") and omit begin.
endShould be a number (Arabic or Roman).
endtermPoints to an element that contains the text for the link. If used, the begin, end, and units attributes are ignored if present.