René Adolphe Schwaller de Lubicz (December 30, 1887 – December 7, 1961), born René Adolphe Schwaller in Alsace-Lorraine, was a French Egyptologist and mystic who popularized the idea of sacred geometry in ancient Egypt during his study of the art and architecture of the Temple of Luxor in Egypt, and his subsequent book The Temple In Man.
Serge Hutin (1927 – 1 November 1997) was a French author of books on esoterica and the occult. He was born in France.
Brad Steiger (February 19, 1936 – May 6, 2018) was an American writer of fiction and non-fiction works on the paranormal, spirituality, UFOs, true crime and biographies. His books sold well to the public but were widely criticized by academics and skeptics for making far-fetched claims without scientific evidence.