Harrison - The California Ceberg (1973), Captive Universe (1967), collected editorials of John Campbell (1965), The Death Effect (1968), Box: 9, Folder: 32. 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/230249 Accessed May 17, 2024.