Tolong jelaskan mengenai Klasifikasi dari Ular Garter

Conant R (1975). A Field Guide to Reptiles and Amphibians of Eastern and Central North America, Second Edition. Boston: Houghton Mifflin Company. xviii + 429 pp. + Plates 1-48.  (hardcover),  (paperback). (Genus Thamnophis, p. 157).

Fitzinger L (1843). Systema Reptilium, Fasciculus Primus, Amblyglossae. Vienna: Braumüller & Seidel. 106 pp. + indices. (Thamnophis, new genus, p. 26). (in Latin).

Goin, Coleman J., Goin, Olive B.; Zug, George R. (1978). Introduction to Herpetology, Third Edition. San Francisco: W.H. Freeman and Company. xi + 378 pp. . (Thamnophis, pp. 132, 156, 326).

Powell R, Conant R, Collins JT (2016). Peterson Field Guide to Reptiles and Amphibians of Eastern and Central North America, Fourth Edition. Boston and New York: Houghton Mifflin Harcourt. xiv + 494 pp., 47 plates, 207 figures. . (Genus Thamnophis, p. 426).

Ruthven AG (1908). "Variation and Genetic Relationships of the Garter-snakes". Bull. U. S. Nat. Mus. 61: 1-201, 82 figures.

Schmidt, Karl P.; Davis, D. Dwight (1941). Field Book of Snakes of the United States and Canada. New York: G.P. Putnam's Sons. 365 pp., 34 plates, 103 figures. (Genus Thamnophis, p. 236).

Stebbins RC (2003). A Field Guide to Western Reptiles and Amphibians, Third Edition. The Peterson Field Guide Series ®. Boston and New York: Houghton Mifflin Company. xiii + 533 pp., 56 plates. . (Genus Thamnophis, pp. 373–374).

Vandenburgh J, Slevin JR (1918). "The Garter-snakes of Western North America". Proc. California Acad. Sci., Fourth Series 8: 181-270, 11 plates.