taxonomy
McLaughlin, S.P. 1982. A revision of the southwestern species of AMSONIA (Apocynaceae). Bulletin Missouri Botanical Garden 69: 336-350.
Lang, B. 2005. Taxonomic assessment of Ashmunella hebardi and Ashmunella mearnsii of the Big Hatchet Mountains, New Mexico. New Mexico Department of Game and Fish Project Number E-57(1-3).
Fletcher, R. 1985. Kuenzler hedgehog cactus (Echinocereus fendleri var. kuenzleri) recovery plan. U.S. Fish and Wildlife Service, Albuqerque, NM. 44 pp.
Lang, B. K. 2001. Status of the Texas hornshell and native freshwater mussels (Unionoidae) in the Rio Grande and Pecos River of New Mexico and Texas. Conservation Services Division, New Mexico Department of Game and Fish.Completion Report. .
Flora of North America Editorial Committee. 1993a. Flora of North America north of Mexico. Vol. 2. Pteridophytes and gymnosperms. Oxford Univ. Press, New York. xvi + 475 pp.
Kartesz, J.T. 1988. A flora of Nevada. Ph.D. dissertation. Univ. of Nevada, Reno. 3 volumes. 1729 pp.
Hodges, R.W. et al., eds. 1983. Check List of the Lepidoptera of America North of Mexico. E.W. Classey Limited and The Wedge Entomological Research Foundation, London. 284 pp.
American Ornithologists' Union (AOU). 1983. Check-list of North American Birds, 6th edition. Allen Press, Inc., Lawrence, Kansas. 877 p.
Honacki, J. H., et al., eds. 1982. Mammal Species of the World: A Taxonomic and Geographical Reference. Allen Press, Inc. and The Association of Systematics Collections, Lawrence, Kansas. 694 pp.
Benson, L. 1982. The Cacti of the United States and Canada. Stanford University Press, Stanford, California. 1044 pp.