The best book I’ve ever seen in the English language is Cuba and its Music: From First Drums to the Mambo by Ned Sublette.  Check it out and get some detail.  Its got so much in detail that you wouldn’t believe it.  He says there is much written by Cuban academcians in the Spanish language, but almost nothing in English.  If you are comfortable reading English and want to learn a WHOLE LOT about Cuban music, get this one.