Azar, B. S. (2004). Understanding and using English grammar. Tp. HCM: Trẻ.
Chicago Style aipamenaAzar, Betty Schrampfer. Understanding and Using English Grammar. Tp. HCM: Trẻ, 2004.
MLA aipamenaAzar, Betty Schrampfer. Understanding and Using English Grammar. Tp. HCM: Trẻ, 2004.
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