José, I think Scott can give you the right suggestion here. I have a lot of books but seldom read them. In the past I have learned a lot from "A modern method for the keyboard study" by James Progris (Berklee Series), but right now I think that the best thing is to analize how great players play the songs you like most and this can be done searching for transcriptions of their songs or studying midifiles of those same tunes, played by really good musicians.
Andrea
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Korg Kronos 61 and PA3X-Pro76, Roland G-70, BK7-m and Integra 7, Casio PX-5S, Fender Stratocaster with Fralin pickups, Fender Stratocaster with Kinman pickups, vintage Gibson SG standard.