American Airman. Milwaukee, Wis.: Antique Airplane Association, September 1957

American Airman. Milwaukee, Wis.: Antique Airplane Association, September 1957, Volume: Gilbert D41. Robert L. Gilbert First Issues collection, Gilbert. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/525132 Accessed December 27, 2025.