The Dark Heart of Time: A Tarzan novel is a novel by American writer Philip José Farmer, authorized by Edgar Rice Burroughs, Inc. Published in 1999, the book was first announced under the title Tarzan's Greatest Secret in 1997. A 2018 reissue of the novel marked the book's first hardcover edition, and was retitled Tarzan and the Dark Heart of Time.
Source · Wikipedia CC BY-SA 4.0