The Source is an excellent addition to any musician's or teacher's library. It is also a very informative guide for people who are looking for a book with good, solid information regarding scales, chords, and how these two work together. The Source provides clear and complete right and left hand piano fingerings for scales, chords, and complete inversions. With over twenty different scales, each written in all twelve keys, The Source is the most complete collection of contemporary and traditional scales ever compiled into one book.