Leather Snake (Tropidonotus leberis: 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.); Stiff Snake (Tropidonotus rigidus: 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.); Stiff Snake (Tropidonotus rigidus: 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.); Green Queen Snake (Tropidonotus rigidus: 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); Stiff Snake (Natrix rigida: 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.); Brown Water Snake (Natrix rigida: Beyer, George. 1900. Louisana herpetology. Proceedings of the Louisiana Society of Naturalists 1897-1899():24-46); Striped Water Snake (Natrix rigida: Schmidt, Karl Peterson and D. D. Davis. 1941. Field Book of Snakes of the United States and Canada. C.P. Putnam and Sons, New York. 365pp.); Striped Water Snake (Natrix rigida: Schmidt, Karl P. 1953. A Check List of North American Amphibians and Reptiles. 6th Edition. University of Chicago Press, Chicago, Illinois. 280pp.); Western Glossy Water Snake (Regina rigida sinicola: Webb, Robert G. 1970. Reptiles of Oklahoma. Stovall Museum, University of Oklahoma Press, Norman. 370pp.);