Walker, E., Elsworth, S., & Nguyễn Văn Phước. (2003). Grammar practice for intermediate students: With answers (New ed.). Tp.HCM: Nxb Trẻ.
Chicago Style aipamenaWalker, Elaine., Steve Elsworth, và Nguyễn Văn Phước. Grammar Practice for Intermediate Students: With Answers. New ed. Tp.HCM: Nxb Trẻ, 2003.
MLA aipamenaWalker, Elaine., Steve Elsworth, và Nguyễn Văn Phước. Grammar Practice for Intermediate Students: With Answers. New ed. Tp.HCM: Nxb Trẻ, 2003.
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