↑Utiger, Urs, Notker Helfenberger, Beat Schätti, Catherine Schmidt, Markus Ruf and Vincent Ziswiler (2002) Molecular systematics and phylogeny of Old World and New World ratsnakes, Elaphe Auct., and related genera (Reptilia, Squamata, Colubridae)., Russ. J. Herpetol. 9 (2): 105-124.
↑Conant,R. & Collins,J.T. (1991) A Field Guide to Reptiles and Amphibians of Eastern/Central North America, 3rd ed., Houghton Mifflin (Boston/New York), xx + 450 p.
↑Dowling, H. G. (1952) A taxonomic study of the ratsnakes, genus Elaphe Fitzinger, IV. A checklist of the American forms., Occ. Pap. Mus. Zool. Univ. Michigan No. 541, 12 pp.
↑ 5.05.1Yarrow,H.C. (1880) Coluber bairdi sp. nov. In: Cope, E.D., On the zoological position of Texas., Bull. US Natl. Mus., No.17: 41
↑ 6.06.1Bisby F.A., Roskov Y.R., Orrell T.M., Nicolson D., Paglinawan L.E., Bailly N., Kirk P.M., Bourgoin T., Baillargeon G., Ouvrard D. (ed.) (2011). "Species 2000 & ITIS Catalogue of Life: 2011 Annual Checklist". Species 2000: Reading, UK. Ginkuhà 24 Septyembre 2012.CS1 maint: multiple names: authors list (link) CS1 maint: extra text: authors list (link)