Cita APA (7th ed.)

Hewings, M., & Goldstein, S. (1998). Pronunciation plus-: Practice through interaction. North american english. Cambridge University Press.

Cita Chicago (17th ed.)

Hewings, Martin, i Sharon Goldstein. Pronunciation Plus-: Practice Through Interaction. North American English. New York, USA: Cambridge University Press, 1998.

Cita MLA (9th ed.)

Hewings, Martin, i Sharon Goldstein. Pronunciation Plus-: Practice Through Interaction. North American English. Cambridge University Press, 1998.