ANYONE OF THEM..if you want to be a great poker player read as many as you can. mark certain things ie. pages that you think you need to study..even the slow ones or maybe just a book about poker or a movie. Knowlege is power the more you have the better off you are.
Super system.. a must.. outdated but usefull
Caro's Book of Poker Tells
.. a must for live players
Every Hand Revealed Gus Hansen...a good read
A Poker Player's Guide to MIXED GAMES..for everyone that plays home games
Positively Fifth Street..A great story it is one of my favorite books
That is just a few. I say grab one that clicks to yah and start reading and don't ever stop....exept to play poker hehe!