PL Omaha High - recommend some books?

[CurryLover]

I've just started to take PLO a bit more seriously and would like to read as much as I can about it. Problem is, there don't seem that many books on it. I think I've read all the most regularly recommended books, and would like some recommendations of books that are good but maybe lesser known. Just to clarify - I am only interested in books that will help me with PLOmaha (i.e. not O8B).

Here are the books that I have already read that have at least some parts in them relevant to PLOmaha:

Ciaffone, Omaha Hold'em
Reuben, How good is your Pot limit Omaha?
Reuben & Ciaffone, Pot Limit and Not Limit Poker
Reuben, How good is your Pot limit Omaha?
Ciaffone, Improve your poker
Mahmood, The science of poker
Helmuth, Play poker like the pros (yes, I know...)

Only the first two books are 100% concerned with Omaha, and only the 2nd one is 100% concerned with PLOmaha. Not exactly an exhaustive list is it? Are there any lesser known gems out there that I should read?