Whitney, N. (1994). Open doors (student's book 1): Có sách. Oxford: Oxford University Press.
Style de citation ChicagoWhitney, Norman. Open Doors (student's Book 1): Có Sách. Oxford: Oxford University Press, 1994.
Style de citation MLAWhitney, Norman. Open Doors (student's Book 1): Có Sách. Oxford: Oxford University Press, 1994.
Attention : ces citations peuvent ne pas être correctes à 100%.