APA (7th ed.) Citation

Darwin, C. (1994). The origin of species by means of natural selection: The descent of man and selection in relation to sex (2nd ed., 5th print.). Encyclopaedia Britannica, Inc..

Chicago Style (17th ed.) Citation

Darwin, Charles. The Origin of Species by Means of Natural Selection: The Descent of Man and Selection in Relation to Sex. 2nd ed., 5th print. Chicago, Ill [etc.]: Encyclopaedia Britannica, Inc., 1994.

MLA (9th ed.) Citation

Darwin, Charles. The Origin of Species by Means of Natural Selection: The Descent of Man and Selection in Relation to Sex. 2nd ed., 5th print. Encyclopaedia Britannica, Inc., 1994.