Keller, D. P. (1987). Interactions I: A speaking activities book. United States: Macmillan Pub Co.
Chicago Style aipamenaKeller, Deborah Poole. Interactions I: A Speaking Activities Book. United States: Macmillan Pub Co, 1987.
MLA aipamenaKeller, Deborah Poole. Interactions I: A Speaking Activities Book. United States: Macmillan Pub Co, 1987.
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