Animal Life in Yellowstone National Park—Vernon Bailey
Yellowstone Information Manual—Fauna—Compiled by Dorr Yeager
Lives of Game Animals—E. T. Seton
Field Book of North American Mammals—H. E. Anthony
Meeting the Mammals—Victor H. Cahalane
A Field Guide to the Mammals—W. H. Burt and R. P. Grossenheider
How to Know the Mammals—E. S. Booth