references has 718 questions, synonyms books, sources and resources and a tag wiki that seems to cover requesting references:
"References" is our generic tag for questions seeking information
about books, papers, presentations, videos of lectures, on-line
tutorials, etc., regarding any subject matter that is on-topic for
reference-request currently has four questions (one of them I just retagged) and no tag wiki.
I propose adding reference-request as a synonym to references. (I don't have five votes, so I'm posting here.) Thoughts?
The meta question Tags for references is related.