Baer, Don, Generalized Language and Thought in the Mentally Retarded, Submitted, September 29, 1978, Box: 3B, Folder: 5. University of Kansas Schiefelbusch Institute for Life Span Studies records, RG 35. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/452323 Accessed July 11, 2025.