Reprints: proceedings of the 3rd congress of the International Association for the Scientific Study of Mental Deficiency, the Hague, 1973, Box: 3, Folder: 4. Personal Papers of Richard Schiefelbusch, PP 458. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/266203 Accessed November 27, 2024.