Fischer, Hank. Wolf Wars, Helena: Falcon Press, 1995.

Goldman, Edward A.; Young, Stanley P. The Wolves of North America. Pt 2. Toronto: General Publishing Co., 1944.

Keiter, Robert B. The Greater Yellowstone Ecosystem. New Haven: Yale University Press, 1991.

Lopez, Barry H. Of Wolves and Men. Canada: Charles Scribner's Sons, 1978.

The Reintroduction of Gray Wolves to Yellowstone National Park and Central Idaho. DEIS. Fish and Wildlife Service and the US Department of the Interior, 1993