APA Citation

Darwin, C. R. 1., & Darwin, C. R. 1. (1975). The origin of species by means of natural selection: The descent of man and selection in relation to sex. Chicago, III.: Encyclopaedia Britannica.

Chicago Style Citation

Darwin, Charles Robert 1809-1882, and Charles Robert 1809-1882 Darwin. The Origin of Species By Means of Natural Selection: The Descent of Man and Selection in Relation to Sex. Chicago, III.: Encyclopaedia Britannica, 1975.

MLA Citation

Darwin, Charles Robert 1809-1882, and Charles Robert 1809-1882 Darwin. The Origin of Species By Means of Natural Selection: The Descent of Man and Selection in Relation to Sex. Chicago, III.: Encyclopaedia Britannica, 1975.

Warning: These citations may not always be 100% accurate.