Walker, E., Elsworth, S., & Nguyễn Văn Phước. (2001). Grammar practice for pre - intermediate students. Tp.HCM: Nxb Trẻ.
Chicago Style aipamenaWalker, Elaine., Steve Elsworth, và Nguyễn Văn Phước. Grammar Practice for Pre - Intermediate Students. Tp.HCM: Nxb Trẻ, 2001.
MLA aipamenaWalker, Elaine., Steve Elsworth, và Nguyễn Văn Phước. Grammar Practice for Pre - Intermediate Students. Tp.HCM: Nxb Trẻ, 2001.
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