Legendary guitarist Pat Martino reveals his concepts of music and approach to improvising in his first book 'Linear Expreaions'. Pat discuaes vertical and horizontal position playing and how to substitute and reduce all chord forms to minor, for purposes
Besides being an amazing player, Pat Martino is an amazing thinker. In this book he explains his concept of converting everything to a minor sound and playing it over the changes. It's an amazing concept and well worth adding to your improvising repertoire.