Programming in Haskell by Graham Hutton. [book website]
The Haskell School of Expression by Paul Hudak. [book website]
Learn You a Haskell for Great Good. [website]
Real World Haskell by Bryan O'Sullivan, Don Stewart, and John Goerzen. [website]
A History of Haskell: Being Lazy With Class by Hudak et al. [paper]
Why functional programming matter by John Hughes. [paper]
How to make ad-hoc polymorphism less ad hoc by Philip Wadler and Stephen Blott. [paper website]
Implementing Type Classes by John Peterson and Mark P. Jones. [paper website]
Imperative functional programming by Simon Peyton Jones and Philip Wadler. [paper]
Tackling the Awkward Squad: monadic input/output, concurrency, exceptions, and foreign-language calls in Haskell by Simon Peyton Jones. [paper]
QuickCheck: a lightweight tool for random testing of Haskell programs by Koen Claessen and John Hughes. [paper website]
Monad transformers and modular interpreters by Liang, Hudak and Jones. [paper website]