APA-referens (7:e uppl.)

Darwin, C., Barrett, P. H., Freeman, R. B., & Darwin, F. (1989). The different forms of flowers on plants of the same species. Pickering.

Chicago-referens (17:e uppl.)

Darwin, Charles, Paul H. Barrett, R. B. Freeman, och Francis Darwin. The Different Forms of Flowers on Plants of the Same Species. London: Pickering, 1989.

MLA-referens (8:e uppl.)

Darwin, Charles, et al. The Different Forms of Flowers on Plants of the Same Species. Pickering, 1989.