Risley, Todd, Day Care for Infants from Walking to Preschool Age, HD 08625-01, October 1, 1973, Box: 68, Folder: 16. 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/455610 Accessed June 02, 2024.