Citazione Stile APA (7a Edizione)

GRAVER, B. (1984). Advanced english practice: With key .-- Ed.2. Oxford University Press.

Citazione stile Chigago Style (17a edizione)

GRAVER, B.D. Advanced English Practice: With Key .-- Ed.2. Oxford: Oxford University Press, 1984.

Citatione MLA (9a ed.)

GRAVER, B.D. Advanced English Practice: With Key .-- Ed.2. Oxford University Press, 1984.