Whitney, N. (1994). Open doors: Student's book 1. Oxford: Oxford University Press.
Trích dẫn kiểu ChicagoWhitney, Norman. Open Doors: Student's Book 1. Oxford: Oxford University Press, 1994.
MLA引文Whitney, Norman. Open Doors: Student's Book 1. Oxford: Oxford University Press, 1994.
警告：这些引文格式不一定是100％准确.