Steelman - The Man They Hanged (1979, 1981), The Great Yellowstone Steamboat Race (1978, 1981, 1980), Box: 21, Folder: 29. 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/230676 Accessed May 16, 2024.