E. D.  Cope, ?A contribution to the herpetology of MexicoProceedings of the American Philosophical Society?, vol. 22, pp. 379-404, 1885.

E. D.  Cope, ?Eleventh contribution to the herpetology of tropical AmericaProc. Amer. Philos. Soc.?, vol. 18, pp. 261-277, 1879.

E. D.  Cope, ?A New Genus of Cystignathidae from Texas?, American Naturalist, vol. 12, no. 4, pp. 252-253, 1878.

E. D.  Cope, ?Tenth contribution to the herpetology of tropical America?, Proceedings of the American Philosophical Society, vol. 17, no. 100, pp. 85-98, 1877.