Here is a list, in no particular order, of books on UFOs and UFOlogy that I have enjoyed reading.
Flying Saucerers A social History of UFOlogy, David Clarke & Andy Roberts
Published by Alternative Albion, 2007.
Out Of The Shadows, David Clarke & Andy Roberts
Published by Piatkus, 2002.
Cosmic Crashes, Nicholas Redfern
Published by Simon & Schuster UK, 1999.
The UFOs That Never Were, Jenny Randles, Andy Roberts & David Clarke
Published by London House, 2000.
Phantoms of the Sky UFOs A Modern Myth?, David Clarke & Andy Roberts
Published by Robert Hale, 1990.
Sky Crash, Brenda Butler, Dot Street, and Jenny Randles
Published by Neville Spearman Ltd, 1984
The UFO Report 1990, Edited By Timothy Good
Published by Sidgwick and Jackson Ltd, 1990
The Scoriton Mystery Did Adamski Return?, Eileen Buckle
Published by Neville Spearman, 1967.
The UFO Experience A Scientific Inquiry, J. Allen Hynek
Published by Abelard-Schuman, 1972.
A Covert Agenda, Nick Redfern
Published by Paraview Special Editions, 2004.
Left at East Gate, Larry Warren & Peter Robbins
Published by Cosimo, 2005.
You Can't Tell The People, Georgina Bruni
Published by Sidgwick & Jackson, 2000.
The Warminster Mystery, Arthur Shuttlewood
Published by Neville Spearman, 1967.
Unidentified Flying Objects, Robert Chapman
Published by Arthur Baker, 1969.
On The Trail Of The Saucer Spies, Nick Redfern
Published by Anomalist Books, 2006.
An American Demonology, Colin Bennett
Published by Critical Vision, 2005.
A Secret Property, Ralph Noyes
Published by Quartet Books, 1985.
Flying Saucers And The Three Men, Albert K. Bender
Published by Nevile Spearman, 1963.
They Knew Too Much About Flying Saucers, Gray Barker
Published by T. Werner Laurie, 1958.
The Report On Unidentified Flying Objects, Edward J. Ruppelt
Published by Ace Books, 1956.
Flying Saucers and Commonsense, Waveney Girvan
Published by Frederick Muller, 1955.
Above Top Secret, Timothy Good
Published by Harper Collins, 1993.
Shockingly Close To The Truth, James W. Moseley & Karl T. Pflock
Published by Prometheus Books, 2002.