Everhart, Sydney E., Joseph S. Ely, and Harold W. Keller. "Evaluation of Tree Canopy Epiphytes and Bark Characteristics Associated with the Presence of Corticolous Myxomycetes." Botany-Botanique 87, no. 5 (2009): 509-517.

Everhart, Sydney E., Harold W. Keller, and Joseph S. Ely. "Influence of Bark Ph on the Occurrence and Distribution of Tree Canopy Myxomycete Species." Mycologia 100, no. 2 (2008): 191-204.

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.

Fanning, Erin, Joseph S. Ely, Thorsten H. Lumbsch, and Harold W. Keller. "Vertical Distribution of Lichen Growth Forms in Tree Canopies of Great Smoky Mountains National Park." Southeastern Naturalist 6, no. sp2 (2007): 83-88.