E Walker. (1995). Grammar practical for intermediate students with answer key: Song ngữ. Tp. HCM: Trẻ.
Παραπομπή Chicago StyleE Walker. Grammar Practical for Intermediate Students With Answer Key: Song Ngữ. Tp. HCM: Trẻ, 1995.
Παραπομπή MLAE Walker. Grammar Practical for Intermediate Students With Answer Key: Song Ngữ. Tp. HCM: Trẻ, 1995.
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