Hadfield, J., & Hadfield, C. (1999). Simple listening activities. Oxford: Oxford University Press.
Chicago Style aipamenaHadfield, Jill, và Charles Hadfield. Simple Listening Activities. Oxford: Oxford University Press, 1999.
MLA aipamenaHadfield, Jill, và Charles Hadfield. Simple Listening Activities. Oxford: Oxford University Press, 1999.
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