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.
Chicago-tyylinen lähdeviittausCullen, Pauline, Vanessa Jakeman, ja Amanda French. The Offical Cambridge Guide to IELTS for Academic & General Training: Student's Book With Answers. New York: Cambridge university press, 2014.
MLA-viiteCullen, Pauline, Vanessa Jakeman, ja Amanda French. The Offical Cambridge Guide to IELTS for Academic & General Training: Student's Book With Answers. New York: Cambridge university press, 2014.
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