I personally think that a central pool (how
central? Should it be common to all languages of Wikipedia, almost
like the Wikimedia Commons?) is a subproject too big to be
implemented inside Wikipedia. For example, in some cases this
pool needs to link to works digitized in Wikisource or in external
digitization projects. And at least Wikiquote and Wikinews should
benefit from using the same "central pool" as Wikipedia. And if
"Wikicat" is set up as a new, separate project, the people who
should be involved there are already considering the global need
(inside and outside of Wikimedia Foundation projects) for new
bibliographic resources. My current guess is that the
demo.openlibrary.org, which runs under the Open Content Alliance
and/or Internet Archive, would be the best place for this.
Wikimedia's answer to Google Scholar? Sounds good. I imagine we could
get quite a lot of websites to use it for all their citations.