1. Brink Jack W. (2016) E-mail message to James Keyser dated May 19 with DStretched photographs of pictograph on Panel 19.
2. Brink Jack W. (2020) E-mail message to James Keyser dated January 11 discussing DStretched photographs from 2016 and 2019 of pictograph on Panel 19.
3. Denig, Edwin (1976) Five Indian Tribes of the Upper Missouri. University of Oklahoma Press, Norman.
4. Armored Horses in Northwestern Plains Rock Art;Greer Mavis;Archaeology In Montana,2019
5. Grinnell, George Bird (1971) By Cheyenne Campfires. University of Nebraska Press, Lincoln.