taxonomy
Kartesz, J. and C. Meacham. 1999. Synthesis of the North American Flora, Version 1.0. North Carolina Botanical Garden.
Correll, D.S., and M.C. Johnston. 1970. Manual of the vascular plants of Texas. Texas Research Foundation, Renner. 1881 pp.
Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Rollins, R.C. 1993a. The Cruciferae of continental North America: Systematics of the mustard family from the Arctic to Panama. Stanford Univ. Press, Stanford, California. 976 pp.
Arnett, Jr., Ross H., ed. 1983. Checklist of the Beetles of North and Central America and the West Indies. Flora and Fauna Publications, Gainesville, Florida. 24 P. (Pertains to all subsequent fasicle updates as well).
Hall, E. R. 1981a. The Mammals of North America, second edition. Vols. I & II. John Wiley & Sons, New York, New York. 1181 pp.
Hobbs, H.H., Jr. H.H. Hobbs III, and M.A. Daniel. 1977. A review of the troglobitic decapod Crustaceans of the Americas. Smithsonian Contributions to Zoology, 244: 1-183.
Luer, C.A. 1975. The native orchids of the United States and Canada excluding Florida. New York Botanical Garden. 361 pp.
Nesom, G.L., and B. Hevron. 1995. Erigeron bistiensis (Asteraceae: Astereae): a new species from northwestern New Mexico. Madrono 42(1): 12-18.
American Ornithologists' Union (AOU). 1957. The AOU check-list of North American birds, 5th ed. Port City Press, Inc., Baltimore, MD. 691 pp.