Out-of-print textbooks that should be reprinted One of the things I'm looking into doing is beginning a Dover-like publishing company for putting out-of-print textbooks back into print in nice, cheap editions for students. So I'd like to ask the mathematicians here who are aware of such books: 

What books that are out of print would you like to see republished in such editions—books for which you think it's a tragedy that they are out of print? 

I think it's a good question for professional mathematicians and would form the basis for the beginnings of my book line. No limit on how many you'd like to suggest. 
I have a ton of such books, but I'll kick it off with the two books I think it's tragic are out of print: 
Functional Analysis, 2nd. ed. by L.V.Kantorovich and G.P. Akilov. 
Notes On Differential Geometry by Noel J.Hicks. (Yes, I know there's a PDF of it floating around online, but a lot of us would like an actual physical book.) 

Theory of Numbers: A Text and Source Book of Problems, Andrew Adler, John E. Coury.
I love this book, but unfortunately it is out of print!
