This is a guide to the history, background and meaning of an unanswered question of our time: Are we alone? It covers associated phenomena such as alien abduction, crop circles, cattle mutilations. and conspiracy theories which surround UFOs from secret Nazi technology to weird CIA plots.

The Mammoth Book of UFOs 2001, Carroll & Graf Publishers, New York, NY

ISBN-13: 9780786708000

Trade paperback

The Mammoth Book of UFO's 2001, Robinson Publishing, London

ISBN-13: 9781841190754