Rupp, S. P., M. C. Wallace, D. Wester, S. Fettig, and R. Mitchell. “EFFECTS OF SIMULATED ELK GRAZING AND TRAMPLING (II): FREQUENCY”. Alces: A Journal Devoted to the Biology and Management of Moose, vol. 37, no. 1, Jan. 2001, pp. 147-61, https://www.alcesjournal.org/index.php/alces/article/view/559.