APA (7th ed.) Citation

Darwin, C. (2004). The origin of the species by means of natural selection. Barnes & Noble Classics.

Chicago Style (17th ed.) Citation

Darwin, Charles. The Origin of the Species by Means of Natural Selection. New York, NY: Barnes & Noble Classics, 2004.

MLA (9th ed.) Citation

Darwin, Charles. The Origin of the Species by Means of Natural Selection. Barnes & Noble Classics, 2004.

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