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
• Boraginaceae and Hydroleaceae of North America Update
• Correll, D. S. & M. C. Johnston. 1970. Man. Vasc. Pl. Texas i–xv, 1–1881. The University of Texas at Dallas, Richardson.
• Dawson, G. 1965. Boraginaceae, Scrophulariaceae, Orobanchaceae, Lentibulariaceae, Acanthaceae in A. Burkart. 4(5): 100–121; 251–298; 304–331. In A. L. Cabrera Fl. Prov. Buenos Aires. Instituto Nacional de Tecnología Agropecuaria, Buenos Aires.
• 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.
• Hickman, J. C. 1993. Jepson Man.: Higher Pl. Calif. i–xvii, 1–1400. University of California Press, Berkeley.
• 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
• Hitchcock, C. H., A. J. Cronquist, F. M. Ownbey & J. W. Thompson. 1984. Ericaceae through Campanulaceae. PartIV: 1–510. In Vasc. Pl. Pacific N.W. University of Washington Press, Seattle.
• 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.
• Voss, E. G. 1996. Michigan Flora, Part III: Dicots (Pyrolaceae-Compositae). Cranbrook Inst. of Science, Ann Arbor.
• Zuloaga, F. O., O. Morrone, M. J. Belgrano, C. Marticorena & E. Marchesi. (eds.) 2008. Catálogo de las Plantas Vasculares del Cono Sur (Argentina, Sur de Brasil, Chile, Paraguay y Uruguay). Monogr. Syst. Bot. Missouri Bot. Gard. 107(1): i–xcvi, 1–983; 107(2): i–xx, 985–2286; 107(3): i–xxi, 2287–3348.