Raven used books has the best selection of academic, literary, and art used books in the boston area. Though smaller than other shops, they seem to be much more careful what they buy and they turn over books like crazy. I always leave with a bag full of excellent books.
Raven Used books in Harvard Square always has great used books. they specialize in Scholarly titles, but I find the literature, poetry, and art book sections always have stuff i want. Prices are also very good and they are nice people working there.
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