White, Clayton M., Nancy J. Clum, Tom J. Cade, and W. Grainger Hunt. 2002. “Peregrine Falcon (Falco peregrinus).” The Birds of North America, edited by Paul G. Rodewald. Ithaca: Cornell Lab of Ornithology. Retrieved from the Birds of North America: https://birdsna.org/Species-Account/bna/species/perfal doi: 10.2173/bna.660