The best Haskell book I have ever read. Simple and straightforward. Allows the reader to do something useful very quickly, and with enough reference for further study (read: pointers to academic papers in the theory of programming languages). Highly recommended.
Bibliographic data
@book{
title = "Programming in Haskell",
author = "Graham Hutton",
publisher = "Cambridge University Press",
year = "2007",
isbn = "0-521-87172-7",
}