Swan, M., & Walter, C. (1997). How English works: A grammar practice book. New York: Oxford University Press.
Chicago Style aipamenaSwan, Michael., và Catherine Walter. How English Works: A Grammar Practice Book. New York: Oxford University Press, 1997.
MLA aipamenaSwan, Michael., và Catherine Walter. How English Works: A Grammar Practice Book. New York: Oxford University Press, 1997.
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