Blackwell, A., & Naber, T. (2007). Open forum 1: Academic listening and speaking. Oxford: Oxford Univ. Press.
Chicago Style aipamenaBlackwell, Angela, và Therese Naber. Open Forum 1: Academic Listening and Speaking. Oxford: Oxford Univ. Press, 2007.
MLA aipamenaBlackwell, Angela, và Therese Naber. Open Forum 1: Academic Listening and Speaking. Oxford: Oxford Univ. Press, 2007.
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