Eckstut, S. (1997). Focus on grammar (Workbook): A basic course for reference and practice,Ngữ pháp Longman trình độ sơ cấp. Tp. Hồ Chí Minh: Nxb. Tp. Hồ Chí Minh.
শিকাগো স্টাইলে সাইটেশনEckstut, Samuela. Focus On Grammar (Workbook): A Basic Course for Reference and Practice,Ngữ Pháp Longman Trình độ Sơ Cấp. Tp. Hồ Chí Minh: Nxb. Tp. Hồ Chí Minh, 1997.
এমএলএ সাইটেশনEckstut, Samuela. Focus On Grammar (Workbook): A Basic Course for Reference and Practice,Ngữ Pháp Longman Trình độ Sơ Cấp. Tp. Hồ Chí Minh: Nxb. Tp. Hồ Chí Minh, 1997.
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