Cullen, P., French, A., & Jakeman, V. (2014). The official Cambridge guide to IELTS: For academic & general training : student's book with answers. Cambridge University Press : Cambridge English Language Assessment.
Chicago-viite (17. p.)Cullen, Pauline, Amanda French, ja Vanessa Jakeman. The Official Cambridge Guide to IELTS: For Academic & General Training : Student's Book with Answers. [Cambridge, England]: Cambridge University Press : Cambridge English Language Assessment, 2014.
MLA-viite (9. p.)Cullen, Pauline, et al. The Official Cambridge Guide to IELTS: For Academic & General Training : Student's Book with Answers. Cambridge University Press : Cambridge English Language Assessment, 2014.
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