Burbrink, Frank T. and Timothy J. Guiher. 2014. Considering gene flow when using coalescent methods to delimit lineages of North American pitvipers of the genus Agkistrodon.Zoological Journal of the Linnean Society, 173: 505–526.
herpsoftexas.org
Travis LaDuc; David Cannatella (2019). "Cottonmouth". Herps of Texas. Austin, Texas. Retrieved 2019-06-04.