Sahanaya, W., & Hughes, T. (2002). IELTS preparation and practice: Practice tests with annotated answer key. Oxford University Press.
Chicago-viite (17. p.)Sahanaya, Wendy, ja Terri Hughes. IELTS Preparation and Practice: Practice Tests with Annotated Answer Key. Victoria: Oxford University Press, 2002.
MLA-viite (8. p.)Sahanaya, Wendy, ja Terri Hughes. IELTS Preparation and Practice: Practice Tests with Annotated Answer Key. Oxford University Press, 2002.
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