APA

McGregor, M., Furniss, M., Bousefield, W., Almas, D., Gravelle, P., & Oakes, R. (1975). Evaluation of the Douglas-fir beetle infestation : North Fork Clearwater River drainage, northern Idaho, 1970-73. : Missoula, Mont. : U.S. Dept. of Agriculture, Forest Service, Northern Region, State and Private Forestry.