I don't know whether there is copyright over a book "format", but I really think "...from A to Z" should become a book series, like "The Complete Guide to the Music of..." This is easily the best reference book ever published about a single artist. It is divided in three parts: the "A-Z" itself (the entries are quite informative and comprehensive), albums (in-depth reviews and reference to alternate versions of songs) and songs (where they can be found in Elton's discography). If only all reference books were like this... That's why I suggest that this format become a series. What about "David Bowie from A-Z"?