Henry Louis Hasse (1913 USA - 1977) was an American science fiction author and fan. He is probably known best for being the co-author of Ray Bradbury's first published story, "Pendulum" (November 1941 in Super Science Stories). Hasse's novelette "He Who Shrank" is anthologized in both the classic 1946 collection Adventures in Time and Space, edited by Raymond J. Healy and J. Francis McComas, and in Isaac Asimov's memoir of 1930s science fiction Before the Golden Age. http://en.wikipedia.org/wiki/Henry_Hasse