"Silent Wings: A Memorial to the Passenger Pigeon", published by The Wisconsin Society of Ornithology, 1947, Box: 98, Folder: 36. Sauer's Gouldiana Research about John Gould and other papers, MS 304. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/205393 Accessed November 24, 2024.