United States Department of Agriculture National Invasive Species Information Center
Rouhe, A., and M. Sytsma. 2007. Feral Swine Action Plan for Oregon (PDF| 1.43 MB) Portland State University Center for Lakes and Reservoirs. Prepared for the Oregon Invasive Species Council.
International Union for Conservation of Nature (IUCN)
Wild Pigs in the United States: Their History, Comparative Morphology, and Current Status by John J. Mayer, I. Lehr Brisbin Jr.
Exotic Animal Field Guide: Nonnative Hoofed Mammals in the United States by Elizabeth Cary Mungall