HoME books

hi. i've in the past few years found myself to be an a: middle earth fan and b: collector of vintage books. right now, i own the 1965 copies of hobbit, fellowship, two towers, and return of the king (unfortunately sans the box), as well as a pretty rad copy of silmarillion. i was wondering, before i buy any mass market sort of thing for the HoME books, when were they first published? i have yet to be able to find that information anywhere. thanks!