Kilgore, Courtney M., Harold W. Keller, Sydney E. Everhart, Angela R. Scarborough, Kenneth L. Snell, Melissa S. Skrabal, Charly Pottorff, and Joseph S. Ely. "Tree Canopy Research and Student Experiences Using the Double Rope Climbing Method." Journal of the Botanical Research Institute of Texas 2, no. 2 (2008): 1309-1336.