Jones, L., & Bùi Quang Đông. (1998). Tài liệu luyện thi bằng proficiency: New progress to proficiency : with full key answers for every excrise and further footnotes for evry unit. Tp. HCM: Trẻ.
शिकागो स्टाइल उद्धरणJones, Leo., और Bùi Quang Đông. Tài Liệu Luyện Thi Bằng Proficiency: New Progress to Proficiency : With Full Key Answers for Every Excrise and Further Footnotes for Evry Unit. Tp. HCM: Trẻ, 1998.
एमएलए उद्धरणJones, Leo., और Bùi Quang Đông. Tài Liệu Luyện Thi Bằng Proficiency: New Progress to Proficiency : With Full Key Answers for Every Excrise and Further Footnotes for Evry Unit. Tp. HCM: Trẻ, 1998.
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