De Cedric Allingham. Frederick Muller Limited, 1954, 144 p.

De Walt Whitman. The Nonesuch Press, 1938, 1114 p.

De Jacques Vallée. And / Or Press, 1979, 244 p.

D'Edward J. Ruppelt. Doubleday and Company, 1956, 316 p.

De Jerome Eden. Exposition Press, 1973, 214 p.

De Orfeo M. Angelucci. Amherst Press, 1955, 168 p.

De John Rimmer. The Aquarian Press, 1984, 160 p.

De David M. Jacobs. Simon and Schuster, 1992, 336 p.

Bigelow Holding Corporation, 1992, 64 p.

De Max B. Miller. 1957, 128 p.

Edited by Gray Barker. Saucerian Books, 1974, 84 p.

De G Delord. 2025, 488 p.

De John M. Saul et Janice A. Glaholm. The Mercurius Press, ...

Dinosauria, 1998, 148 p.