Pangborn - A Mirror for Observers (1964, 1971, 1972, 1974, 1976, 1977, 1979, 1983), Box: 16, Folder: 23. 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/322017 Accessed May 19, 2024.