The Communication Perspective: Thoughts on the Future for People with Developmental Disabilities, H.R. Turnbull, October 1991, Box: 14, Folder: 66. Personal papers of Rud Turnbull, PP 511. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/305356 Accessed June 20, 2025.