Kucera, D. R., & Orr, P. W. (1980). Spruce budworm in the eastern United States. U.S. Dept. of Agriculture, Forest Service.
Chicago Style (17th ed.) CitationKucera, Daniel R., and Peter W. Orr. Spruce Budworm in the Eastern United States. [Washington, D.C.?]: U.S. Dept. of Agriculture, Forest Service, 1980.
MLA (9th ed.) CitationKucera, Daniel R., and Peter W. Orr. Spruce Budworm in the Eastern United States. U.S. Dept. of Agriculture, Forest Service, 1980.
Warning: These citations may not always be 100% accurate.