Cita APA (7th ed.)

Darwin, C., & Beer, G. (1996). The origin of species. Oxford University Press.

Cita Chicago (17th ed.)

Darwin, Charles, i Gillian Beer. The Origin of Species. Oxford: Oxford University Press, 1996.

Cita MLA (9th ed.)

Darwin, Charles, i Gillian Beer. The Origin of Species. Oxford University Press, 1996.