Dickson - Spacepaw (1972), Spacial Delivery (1961, 1970), Pilgrim (1968), Planet Run (1965, 1976), Box: 5, Folder: 30. 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/230137 Accessed November 23, 2024.