Singer, Francis J., Dale Kenneth Otto, Alan R. Tipton, and Charles P. Hable. "Home Ranges, Movements, and Habitat Use of European Wild Boar in Tennessee." The Journal of Wildlife Management 45, no. 2 (1981): 343-353.

Otto, Dale Kenneth. Day Beds and Observations at a Farrowing Nest of European Wild Boar in Tennessee. Blacksburg, VA: Virginia Polytechnic Institute and State University, 1979.

Singer, Francis J., Dale Kenneth Otto, Alan R. Tipton, and Charles P. Hable. Home Ranges and Habitat Use of European Wild Boar. Gatlinburg, TN: U. S. Department of the Interior, National Park Service, Uplands Field Research Lab, 1979.

Otto, Dale Kenneth. Movements, Activity Patterns, and Habitat Preferences of European Wild Boar in Great Smoky Mountains National Park. Blacksburg, Virginia: Virginia Polytechnic Institute, 1978.