Cameron, P. (2011). Prepare for IELTS: Academic practice tests. Thành phố Hồ Chí Minh: Trẻ.
Chicago-tyylinen lähdeviittausCameron, Penny. Prepare for IELTS: Academic Practice Tests. Thành phố Hồ Chí Minh: Trẻ, 2011.
MLA-viiteCameron, Penny. Prepare for IELTS: Academic Practice Tests. Thành phố Hồ Chí Minh: Trẻ, 2011.
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