APA (7th ed.) Zitazioa

Swan, M. (1980). Practical english usage (1a. ed.). Oxford University Press.

Chicago Style (17th ed.) Zitazioa

Swan, Michael. Practical English Usage. 1a. ed. Oxford: Oxford University Press, 1980.

MLA (9th ed.) Zitazioa

Swan, Michael. Practical English Usage. 1a. ed. Oxford University Press, 1980.