There is a overlap of 13 posts.
The problem I see with references is some users think it refers to citations and others think it refers to reference letters. I think we probably need to decide which one is which, retag the questions that do not belong, and add a tag wiki and synonym. It might be best to come up with a list and let the diamond mods do a mass retag to avoid flooding the front page.
I think tagging is one area we are weak on. I have a bunch of proposed synonyms that have just been sitting in voted on. Some I am not sure about, but others are pretty obvious in my mind.