APA

Harris M., Mackay B. K., . (19861974). A field guide to the birds of Galápagos. Grafton Street, London: Collins.

Chicago

Harris Michael, Mackay Barry Kent, . 19861974. A field guide to the birds of Galápagos. Grafton Street, London: Collins.

Harvard

Harris M., Mackay B. K., . (19861974). A field guide to the birds of Galápagos. Grafton Street, London: Collins.

MLA

Harris Michael, Mackay Barry Kent, . A field guide to the birds of Galápagos. Grafton Street, London: Collins. 19861974.