Prairie Water Snake (Regina grahamii: Cooper, James G., George Suckley, William Cooper, George Gibbs, Asa Gray, and John L. Le Conte. 1859. The natural history of Washington territory, with much relating to Minnesota, Nebraska, Kansas, Oregon, and California, between the thirty-sixth and forty-ninth parallels of latitude, being those parts of the final reports on the survey of the Northern Pacific railroad route, containing the climate and physical geography, with full catalogues and descriptions of the plants and animals collected from 1853 to 1857. Bailliere Bros., London, H. Bailliere;, New York, New York. pp.); Graham's Snake (Tropidonotus grahami: Jordan, David Starr. 1876. Manual of the Vertebrates of the Northern United States: Including the District East of the Mississippi River, and North of North Carolina and Tennessee, Exclusive of Marine Species. Jansen, McClurg, and Company, Chicago, Illinois.. 342pp.); Graham's Water Snake (Tropidonotus grahamii: Yarrow, Henry C. 1876. List of Skeletons and Crania in the Section of Comparative Anatomy of the United States Army Medical Museum for use during the International Exhibition of 1876 in Connection with the Representation of the Medical Department U.S. Army. Army Medical Museum, Washington, D. C. pp.); Graham's Snake (Tropidonotus grahami: Jordan, David S. 1878. Manual of the Vertebrates of the Northern United States: Including the District East of the Mississippi River, and North of North Carolina and Tennessee, Exclusive of Marine Species. Second Edition, Revised, and Enlarged. Jansen, McClurg & Company, Chicago. pp.); Graham's Queen Snake (Tropidonotus grahami: Yarrow, Henry C. 1882. Check list of North American Reptilia and Batrachia with catalogue of specimens in U. S. National Museum. Bulletin of the United States National Museum (24):1-249); Graham's Water Snake (Natrix grahamii: Hay, Oliver P. 1892. Batrachians and Reptiles of the State of Indiana. Pages 409-624 in 17th Annual Report of the Indiana Department of Geology and Natural Resources, William B. Burford, Printer and Binder, Indianapolis, Indiana. pp.); Graham's Queen Snake (Natrix grahamii: Branson, Edwin B. 1904. Snakes of Kansas. University of Kansas Science Bulletin 2(13):353-430); Graham's Water-snake (Natrix grahamii: Hurter, Julius. 1911. Herpetology of Missouri. Transactions of the Academy of Science St. Louis 20(5):59-274); Graham's Water Snake (Natrix grahami: Schmidt, Karl P. 1953. A Check List of North American Amphibians and Reptiles. 6th Edition. University of Chicago Press, Chicago, Illinois. 280pp.);