Columbia: Smithsonian Institution. xvi + 172 pp. (Rena humilis, new species, p. 143). Behler JL, King FW (1979). The Audubon Society Field Guide to North American Reptiles and Amphibians. New York: Alfred A. Knopf. 743 pp. . (Leptotyphlops humilis, pp. 584–585 + Plate 457). Boulenger GA (1893). Catalogue of the Snakes in the British Museum (Natural HIstory). Volume I., Containing the Families Typhlopidæ, Glauconiidæ... London: Trustees of the British Museum (Natural History). (Taylor and Francis, printers). xiii + 448 pp. + Plates I-XXVIII. (Glauconia humilis, pp. 70–71). Conant R (1975). A Field Guide to Reptiles and Amphibians of Eastern and Central North America, Second Edition. Boston: Houghton Mifflin. xviii + 429 pp. (hardcover), (paperback). (Leptotyphlops humilis, pp. 137–138, Figure 31 + Map 121). Klauber LM (1940). "The Worm Snakes of the Genus Leptotyphlops in the United States and northern Mexico". Trans. San Diego Soc. Nat. Hist. 9: 87-162. 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. . (Rena humilis, pp. 361–363, Figure 172). Schmidt KP, Davis DD (1941). Field Book of Snakes of the United States and Canada. New York: G.P. Putnam's Sons. 365 pp. (Leptotyphlops humilis, pp. 94–95). Stebbins RC (2003). A Field Guide to Western Reptiles and Amphibians, Third Edition. The Peterson Field Guide Series ®. Boston & New York: Houghton Mifflin. xiii + 533 pp. . (Leptotyphlops humilis, pp. 340–341 + Plate 42 + Map 128). Stejneger L, Barbour T (1917). A Check List of North American Amphibians and Reptiles. Cambridge, Massachusetts: Harvard University Press. 125 pp. (Siagonodon humilis, p. 73). Wright AH, Wright AA (1957). Handbook of Snakes of the United States and Canada. Ithaca and London: Comstock Publishing Associates, a division of Cornell University Press. 1,105 pp. (in 2 volumes). (Leptotyphlops humilis, pp. 43–50, Figure 12 + Map 7 on p. 39). External links iNaturalist page humilis Reptiles of the United States Reptiles of Mexico Taxa named by Charles Frédéric Girard Taxa named by Spencer Fullerton Baird Reptiles described in 1853