Harrison, M., & Kerr, R. (1998). Proficiency practice tests: With answers. New York: Oxford University Press.
Chicago Style aipamenaHarrison, Mark., và Rosalie Kerr. Proficiency Practice Tests: With Answers. New York: Oxford University Press, 1998.
MLA aipamenaHarrison, Mark., và Rosalie Kerr. Proficiency Practice Tests: With Answers. New York: Oxford University Press, 1998.
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