The following bibliography has been generated by bringing together all references provided by our content partners. There may be duplication.

References

• 1996. database, The PLANTS Database
• 1996. database, NODC Taxonomic Code
• 2000. database, The PLANTS Database
• Apocynaceae of North America Update
• Bailey, L. H. & E. Z. Bailey. 1976. Hortus Third i–xiv, 1–1290. MacMillan, New York.
• CONABIO. 2009. Catálogo taxonómico de especies de México. 1. In Capital Nat. México. CONABIO, Mexico City.
• Correll, D. S. & M. C. Johnston. 1970. Man. Vasc. Pl. Texas i–xv, 1–1881. The University of Texas at Dallas, Richardson.
• Cronquist, A. J., A. H. Holmgren, N. H. Holmgren, J. L. Reveal & P. K. Holmgren. 1984. Vascular Plants of the Intermountain West, U.S.A. 4: 1–573. In A. J. Cronquist, A. H. Holmgren, N. H. Holmgren, J. L. Reveal & P. K. Holmgren (eds.) Intermount. Fl. Hafner Pub. Co., New York.
• Fernald, M. 1950. Manual (ed. 8) i–lxiv, 1–1632. American Book Co., New York.
• Gleason, H. A. & A. J. Cronquist. 1991. Man. Vasc. Pl. N.E. U.S. (ed. 2) i–910. New York Botanical Garden, Bronx.
• Gleason, H. A. 1968. The Sympetalous Dicotyledoneae. vol. 3. 596 pp. In H. A. Gleason Ill. Fl. N. U.S. (ed. 3). New York Botanical Garden, New York.
• Great Plains Flora Association. 1986. Fl. Great Plains i–vii, 1–1392. University Press of Kansas, Lawrence.
• Hilty, J. Editor. 2013. Illinois Wildflowers. World Wide Web electronic publication. flowervisitors.info, version 04/2013.
  See: Botanical Terminology and Line Drawings,  Ecological Terminology,  Website Description,  Links to Other Websites,  Reference Materials
• Hilty, J. Editor. 2013. Insect Visitors of Illinois Wildflowers.   World Wide Web electronic publication. illinoiswildflowers.info, version (05/2013)  
  See:   Abbreviations for Insect Activities,   Abbreviations for Scientific Observers,   References for behavioral observations
• Image metadata at Bioimages (http://bioimages.vanderbilt.edu/)
• Long, R. W. & O. K. Lakela. 1971. Fl. Trop. Florida i–xvii, 1–962. University of Miami Press, Coral Cables.
• Marticorena C & R Rodríguez . 1995-2005. Flora de Chile. Vols 1, 2(1-3). Ed. Universidad de Concepción, Concepción. 351 pp., 99 pp., 93 pp., 128 pp. Matthei O. 1995. Manual de las malezas que crecen en Chile. Alfabeta Impresores. 545 p.
• Orrell T. (custodian) (2013). ITIS Regional: The Integrated Taxonomic Information System (version Apr 2011). In: Species 2000 & ITIS Catalogue of Life, 11th March 2013 (Roskov Y., Kunze T., Paglinawan L., Orrell T., Nicolson D., Culham A., Bailly N., Kirk P., Bourgoin T., Baillargeon G., Hernandez F., De Wever A., eds). Digital resource at www.catalogueoflife.org/col/. Species 2000: Reading, UK.
• Radford, A. E., H. E. Ahles & C. R. Bell. 1968. Man. Vasc. Fl. Carolinas i–lxi, 1–1183. University of North Carolina Press, Chapel Hill.
• Scoggan, H. J. 1979. Dicotyledoneae (Loasaceae to Compositae). Part 4. 1117–1711 pp. In Fl. Canada. National Museums of Canada, Ottawa.
• Small, J. K. 1933. Man. S.E. Fl. i–xxii, 1–1554. Published by the Author, New York.
• Voss, E. G. 1996. Michigan Flora, Part III: Dicots (Pyrolaceae-Compositae). Cranbrook Inst. of Science, Ann Arbor.
• Woodson, J. R. E. 1954. The North American species of Asclepias L. Ann. Missouri Bot. Gard. 41(1): 1–211.
• Wunderlin, R. P. 1998. Guide Vasc. Pl. Florida i–x, 1–806. University Press of Florida, Gainseville.