Simak - All Flesh is Grass (1974, 1976), All the Traps on Earth (1961, 1962, 1963), Box: 19, Folder: 59. Corporate Papers of the Robert Mills Literary Agency, MS 307. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/230611 Accessed May 18, 2024.