Report of Consensus Conference on Principles of Family Research, H.R. Turnbull and A. Turnbull, 1989, Box: 1, Folder: 43. Personal papers of Rud Turnbull, PP 511. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/304796 Accessed June 22, 2025.