Cullen, P., Jakeman, V., & French, A. (2014). The offical Cambridge guide to IELTS for academic & general training: Student's book with answers. New York: Cambridge university press.
Trích dẫn kiểu ChicagoCullen, Pauline, Vanessa Jakeman, và Amanda French. The Offical Cambridge Guide to IELTS for Academic & General Training: Student's Book With Answers. New York: Cambridge university press, 2014.
Trích dẫn MLACullen, Pauline, Vanessa Jakeman, và Amanda French. The Offical Cambridge Guide to IELTS for Academic & General Training: Student's Book With Answers. New York: Cambridge university press, 2014.
Cảnh báo: Các trích dẫn này có thể không phải lúc nào cũng chính xác 100%.