Cita APA (7th ed.)

Le Guin, U. K. (1979). The Earthsea trilogy. Penguin Books.

Cita Chicago (17th ed.)

Le Guin, Ursula K. The Earthsea Trilogy. Harmondsworth, England ; Ringwood, Vic.: Penguin Books, 1979.

Cita MLA (8th ed.)

Le Guin, Ursula K. The Earthsea Trilogy. Penguin Books, 1979.