Reuben and Ciaffone?
Didn't they write a seminal one?
p.s try elblondies tapes..link on home page!!
I hate the Reuben one.
The Reuben and Ciaffone one is Pot and No-Limit Poker - not an Omaha specific book but a very good book on 'big bet' poker in general.
Ciaffone also has a book out called Omaha Poker - The Action Game, which is another good read. It covers Omaha 8 as well as high only.
The Reuben solo book, How Good is your Pot Limit Omaha, is a multi-choice question format. Personally, I didn't like it but others seem to. I just found the format of the book difficult to deal with and its that which sticks in the mind, rather than any of the advice it offered.