Cita APA (7th ed.)

Fitter, R. (1967). The Penguin dictionary of british natural history. Penguin Books.

Cita Chicago (17th ed.)

Fitter, Richard. The Penguin Dictionary of British Natural History. Londres: Penguin Books, 1967.

Cita MLA (9th ed.)

Fitter, Richard. The Penguin Dictionary of British Natural History. Penguin Books, 1967.