Expert F# 2.0, Don Syme, 2010
Programming F#, Chris Smith, O’Reilly, 2010
Here is an introduction to Microsoft’s F# functional language. Legendary O’Reilly quality, 350 pages.
Real-world Functional Programming With Examples in F# and C#, Tomas Petricek, , Manning, 2010
For programmers using Microsoft’s F# functional language. 500 pages.
Real World Haskell, Bryan O’Sullivan, O’Reilly, 2008
Haskell is an advanced purely functional programming language. Read the book online here. Sorry, it is not yet at the OPL.