APA (7th ed.) Zitazioa

Hewings, M. (1999). Pronunciation plus: Practice through interaction. North American English. Teacher's Manual. Cambridge University Press.

Chicago Style (17th ed.) Zitazioa

Hewings, Martin. Pronunciation Plus: Practice Through Interaction. North American English. Teacher's Manual. New York, USA: Cambridge University Press, 1999.

MLA (9th ed.) Zitazioa

Hewings, Martin. Pronunciation Plus: Practice Through Interaction. North American English. Teacher's Manual. Cambridge University Press, 1999.