Funded by the National Science Foundation PEET program (Partnerships for Enhancing Expertise in Taxonomy)
Ciesla, W. M., J. E. Dewey, and S. Tunnock. 1971. Northern Rocky Mountains (R-1). Pages 16-21 in A. E. Landgraf, Forest insect conditions in the United States, 1970. United States Department of Agriculture, Forest Service. vi + 44 p.