APA

Moorehead A., . (1971). Darwin and the Beagle. New York: Penguin Books.

Chicago

Moorehead Alan, . 1971. Darwin and the Beagle. New York: Penguin Books.

Harvard

Moorehead A., . (1971). Darwin and the Beagle. New York: Penguin Books.

MLA

Moorehead Alan, . Darwin and the Beagle. New York: Penguin Books. 1971.