The ePub version of Real World Haskell by Bryan O'Sullivan, Don Stewart, and John Goerzen
Pack them all with zip, rename it to .epub, and enjoy! Haskell is a magical language, which is no doubt worth of studying.
Thanks to Bryan O'Sullivan, Don Stewart, and John Goerzen.
Thanks to @bgschaid, now we have a more standard epub at https://keybase.pub/bgschaid/RealWorldHaskell.epub