BioStor
 | Descriptions of new species of reptiles inhabiting North America E Hallowell (1852) Proc. Acad. Nat. Sci. Philadelphia 6: 177-182 |
 | Notes and descriptions of new and little-known species of American reptiles E D Cope (1860) Proc. Acad. Nat. Sci. Philadelphia 12: 339-345 |
 | Descriptions of reptiles from tropical America and Asia E D Cope (1860) Proc. Acad. Nat. Sci. Philadelphia 1860: 368-374 |
 | Contributions to the ophiology of Lower California, Mexico and Central America E D Cope (1861) Proc. Acad. Nat. Sci. Philadelphia 13: 292-306 |
 | Notes upon some reptiles of the Old World E D Cope (1862) Proc. Acad. Nat. Sci. Philadelphia 14: 337-344 |
 | On the Reptilia and Batrachia of the Sonoran Province of the Nearctic Region E D Cope (1867) Proceedings of the Academy of Natural Sciences of Philadelphia 18: 300-314 |
 | Notes on the geographical distribution of batrachia and reptilia in western North America E D Cope (1883) Proc. Acad. Nat. Sci. Philadelphia 35: 10-35 |
 | Thirteenth contribution to the herpetology of tropical America E D Cope (1886) Proc. Amer. Philos. Soc. 23: 271-287 |
 | A critical review of the characters and variations of the snakes of North America E D Cope (1892) Proc. US Natl. Mus. 14: 589-694 |
 | A Review of the Genera and Species of American Snakes, North of Mexico Arthur Erwin Brown (1901) Proceedings of The Academy of Natural Sciences of Philadelphia 53: 10-110 |
 | The reptiles and batrachians of Victoria and Refugio Counties, Texas John K Strecker (1908) Proc. Biol. Soc. Wash. 21: 47-52 |
 | Generic types of nearctic Reptilia and Amphibia A E Brown (1908) Proceedings of the Academy of Natural Sciences of Philadelphia 60: 112-127 |
 | The Gopher-snakes of Western North America John Van Denburgh and Joseph R Slevin (1919) Proceedings of the Calaifornia Academy of Sciences 9: 197-220 |
 | Variations and relationships in the snakes of the genus Pituophis Olive Griffith Stull (1940) Bulletin of the United States National Museum 175: 1-225 |
 | The glossy snake, Arizona, with descriptions of new subspecies Laurence M Klauber (1946) Transactions of the San Diego Society of Natural History 10: 311-398 |
 | Fourth contribution to the herpetology of San Luis Potosà E H Taylor (1953) University of Kansas Science Bulletin 35: 1587-1614 |
 | Type specimens of reptiles and amphibians in the United States National Museum (1961) Bulletin of the United States National Museum 220: 1-291 |