Heron, Loon, Owl, Penguins, and Puffins, 1983 - 1994, Box: 5, Folder: 23. Natural History Art and Illustration by D. D. Tyler, MS 337. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/310584 Accessed June 23, 2025.