Program Project, Communication Research with Retarded Children, D. M. Baer, HD-00870, Final Report, July 6, 1983, Box: 61, Folder: 2. 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/455389 Accessed May 18, 2025.