ulink.footnotes
boolean
ulink.footnotes
Generate footnotes for ulinks?
Description
If non-zero, and if ulink.show also is non-zero,
the URL of each ulink will appear as a footnote.
DocBook 5 does not have an ulink element. When processing 
DocBoook 5 documents, ulink.footnotes applies to all inline 
elements that are marked up with xlink:href attributes 
that point to external resources.