1. Alexander, R.R., 1966. Site Indexes for Lodgepole Pine, with Corrections for Stand Density: Instructions for Field Use. US Forest Service Research Paper RM 24, USDA Rocky Mountain Forest and Range Experiment Station, Fort Collins, CO, p. 7.
2. Alexander, R.R., 1986. Silvicultural Systems and Cutting Methods for Old-Growth Lodgepole Pine Forests in the Central Rocky Mountains. Rocky Mountain Forest and Range Experiment Station, General Technical Report 127, Fort Collins, CO, p. 31.
3. Subalpine fir;Alexander,1990
4. Alexander, R.R., Watkins, R.K., 1977. The Fraser Experimental Forest, Colorado. USDA Forest Service General Technical Report RM 40, USDA Rocky Mountain Forest and Range Experiment Station, p. 32.
5. Amman, G.D., Lessard, G.D., Rasmussen, L.A., O’Neil, C.G., 1988. Lodgepole Pine Vigor, Regeneration, and Infestation by Mountain Pine Beetle Following Partial Cutting on the Shoshone National Forest, Wyoming. USDA Forest Service, Intermountain Forest and Range Experiment Station, Research Paper INT-396, p. 8.