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

References

• 1. National Biodiversity Network Species Dictionary (Feb 2003) http://www.nhm.ac.uk/nbn/
• 2. Clapham, A.R., Tutin, T.G. & Moore, D.M. (1987) Flora of the British Isles. 3rd Edition. Cambridge University Press, Cambridge.
• 3. Preston, C.D., Pearman, D.A. & Dines, T.D. (2002) The New Atlas of the British and Irish Flora. Oxford University Press, Oxford.
• 4. Native Wild Flowers of the North Dakota Grasslands (Feb 2003) http://www.npwrc.usgs.gov/resource/literatr/wildflwr/species/camprotu.htm
• 5. Mabey, R. (1996) Flora Britannica. Sinclair-Stevenson, London.
• 6. Press, B. & Gibbons, B (1993) Photographic field guide to wild flowers of Britain and Europe. New Holland Publishers (UK) Ltd, London.
• Abrams, L. & R. S. Ferris. 1960. Bignonias to Sunflowers. 4: 732 pp. In L. Abrams Ill. Fl. Pacific States. Stanford University Press, Stanford.
• Anonymous. 1986. List-Based Rec., Soil Conserv. Serv., U.S.D.A. Database of the U.S.D.A., Beltsville.
• Böcher, T. W. 1978. Greenlands Flora 326 pp.
• Cody, W. J. 1996. Fl. Yukon Terr. i–xvii, 1–669. NRC Research Press, Ottawa.
• 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.
• Gleason, H. A. & A. Cronquist. 1991. Man. Vasc. Pl. N.E. U.S. (ed. 2) i–lxxv, 1–910. 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. 2010. Insect Visitors of Illinois Wildflowers. World Wide Web electronic publication. flowervisitors.info, version (09/2010).
  See: Abbreviations for Insect Activities, Abbreviations for Scientific Observers, References for behavioral observations
• Hitchcock, C. L., A. Cronquist, M. Ownbey & J. W. Thompson. 1984. Ericaceae through Campanulaceae. Part IV. 510 pp. In Vasc. Pl. Pacific N.W. University of Washington Press, Seattle.
• Hultén, E. 1968. Fl. Alaska i–xxi, 1–1008. Stanford University Press, Stanford.
• Isosyntype: Gray, A. 1886. Syn. Fl. N. Amer. 2: 395.
• Lammers, T. G. 1994. Prodromus Monographiae Campanuloidearum.
• Lammers, Thomas G. 2007. World Checklist and Bibliography of Campanulaceae. ix + 675
• 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.
• Moss, E. H. 1983. Fl. Alberta (ed. 2) i–xii, 1–687. University of Toronto Press, Toronto.
• Munz, P. A. & D. D. Keck. 1959. Cal. Fl. 1–1681. University of California Press, Berkeley.
• Porsild, A. E. & W. Cody. 1980. Vasc. Pl. Continental Northw. Terr. Canada i–viii, 1–607. National Museum of Natural Sciences, Ottawa.
• Scoggan, H. J. 1979. Dicotyledoneae (Loasaceae to Compositae). Part 4. 1117–1711 pp. In Fl. Canada. National Museums of Canada, Ottawa.
• Shetler, Stanwyn G. 1982. Phanerogamarum Monographiae Tomus XI: Variation and Evolution of the Nearctic Harebells (Campanula subsect. Heterophylla). 516
• Voss, E. G. 1996. Michigan Flora, Part III: Dicots (Pyrolaceae-Compositae). Cranbrook Inst. of Science, Ann Arbor.
• Welsh, S. L. 1974. Anderson's Fl. Alaska Adj. Parts Canada i–xvi, 1–724. Brigham Young University Press, Provo.
• Zuloaga, F. O. 1997. Catálogo de las plantas vasculares de la Argentina. Monogr. Syst. Bot. Missouri Bot. Gard. 74(1–2): 1–1331.
• 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.