Cita APA (7th ed.)

Darwin, C., Barrett, P. H., & Freeman, R. B. (1986). The geology of the voyage of H. M. S. beagle, pt. 3: Geological observations on South America. Pickering.

Cita Chicago (17th ed.)

Darwin, Charles, Paul H. Barrett, i R. B. Freeman. The Geology of the Voyage of H. M. S. Beagle, Pt. 3: Geological Observations on South America. London: Pickering, 1986.

Cita MLA (8th ed.)

Darwin, Charles, et al. The Geology of the Voyage of H. M. S. Beagle, Pt. 3: Geological Observations on South America. Pickering, 1986.