- ????: Le Livre des crnes, Pocket Mass market paperback, in French as Le Livre des Crnes
- ????: Voyage au bout de l'esprit, Omnibus Hard cover book, ISBN 2258040582, in French as Le livre des crnes
- 1972: The Book of Skulls, Signet Mass market paperback, 191 pp.
- 1972: The Book of Skulls, Scribner's Hard cover book, 222 pp.
- 1975: Vacanze nel Deserto, Dall'Oglio Trade paperback, in Italian
- 1976: Het Boek der Schedelen, Scala , ISBN 90-6221-451-7, 236 pp., in Dutch
- 1978: The Book of Skulls, Gollancz Hard cover book
- 1979: The Book of Skulls, Berkley Mass market paperback, 208 pp.
- 1980: Bruderschaft der Unsterblichen, Moewig Mass market paperback, in German
- 1981: The Book of Skulls, Coronet Mass market paperback
- 1983: The Book of Skulls, Bantam Mass market paperback, 196 pp.
- 1987: The Book of Skulls, New English Library Mass market paperback, 222 pp.
- 1991: Vacanze nel Deserto, Trade paperback, in Italian
- 1991: The Book of Skulls/Nightwings/Dying Inside, QPB Trade paperback, 222 pp.
- 1998: Voyage au bout de l'esprit, Omnibus Mass market paperback, ISBN 2258049202, 904 pp., in French as Le livre des crnes
- 1999: The Book of Skulls, Gollancz Trade paperback, ISBN 1857989147, 222 pp.
- 1999: The Book of Skulls, Millennium Mass market paperback, ISBN 1857989147, 222 pp.
- 2006: The Book of Skulls, Mass market paperback
(from Signet 1972)
From the Book of Skulls comes the secret of life:
"The Ninth Mystery is this: that the price of a life must always be a life. Know, O Nobly-Born, that eternities must be balanced by extinctions, and therefore we ask of thee that the ordained balance be gladly sustained. Two of thee we undertake to admit to our fold. Two must go into darkness... Is there one among thee who will relinquish eternity for his brothers of the four-sided figure...? And is there one among thee whom his comrades are prepared to sacrifice...? Let the victims choose themselves..."
Four college students journey into the desert seeking the Brotherhood of the Skull and eternal life. But whether the promise of eternal life is real, and which two must die so that the others may attain immortality, only the grinning skull among the rocks can say for sure...
[None on record]