author-year citations

Hi,
I've got my citations in my docbook document and a docbook xml formatted bibliography. I can create the bibliography myself in postprocessing (using lxml and python), but I'm stumped on how to get author-year style citations.

I have a book of many chapters, with each chapter having its own bibliography.  However,  I need to process the book as a whole since I need htmlhelp and a full index and toc xml files for later processing.

I wonder if it is too hard to write the xsl  to convert the citation to html in the author-year style?
Is that too big of a task for an XSL newbie?

thanks,
--Tim Arnold