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---, Stairways to the Stars: Skywatching in Three Great Ancient Cultures. New York: Wiley, 1999.

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---, The Eyes of the Sphinx: The Newest Evidence of Extraterrestrial Contact in Ancient Egypt. New York: Putnam, 1996.

---, The Gods and Their Grand Design. New York: Putnam, 1984.

---, In Search of Ancient Gods: My Pictorial Evidence for the Impossible. New York: Delacorte...