Dellar, H., & Walkley, A. (2010). Pre-Intermediate Outcomes: Student's Book. Heinle, Cengage Learning EMEA.
Chicago Style aipamenaDellar, Hugh, and Andrew Walkley. Pre-Intermediate Outcomes: Student's Book. Hampshire, United Kingdom: Heinle, Cengage Learning EMEA, 2010.
MLA aipamenaDellar, Hugh, and Andrew Walkley. Pre-Intermediate Outcomes: Student's Book. Heinle, Cengage Learning EMEA, 2010.
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