docbook and rdf

Since the defnitions of docbook elements is so stable,
is it feasible to utilise them as rdf properties?
I need to specify a published date and place and docbook neatly provides
this.

What suggested url might I use to ensure it's clear I'm referring to 
the docbook elements? tdg seems very temporally bound. Is it right
for this purpose?

Agreed a year/version should constrain the definition, allowing
schema development, but a firm www.docbook.org/2005/xx/publisher
might suffice to ensure its
http://www.docbook.org/tdg5/en/html/publisher.html I'm referring to?
I'm surmising that xx might be used for a docbook version, something
like that.

Comments?
-- 
Regards, 

Dave Pawson
XSLT + Docbook FAQ
http://www.dpawson.co.uk