Book of Thoth
(not specifically mentioned by Lovecraft) According to L. Sprague de Camp, "The Book of Thoth"'s first appearance is in an ancient Egyptian tale, 'The Story of Setnau Khaemuast,' known from a Ptolemaic papyrus but probably much older. According to this novel, this book of mightly spells was originally penned by the Egyptian ibis-headed god of wisdom, Tehuti or Thoth (sometimes called Hermes Trimegistus). When the papyrus was published early in this century, fantasy writers seized upon the Book of Thoth as a prop for their stories. It plays a role in Sax Rohmer's "Brood of the Witch Queen" (1924) and probably inspired Chambers to create his forbidden book "The King in Yellow."
See also: Hermes Trimegistus