Koch, R. S., & Rachel Spack Koch. (1997). Focus on Grammar An Course for Reference and Practice. Tp. Hồ Chí Minh: Nxb. Tp. Hồ Chí Minh.
シカゴスタイル引用形Koch, Rachel Spack, , Rachel Spack Koch. Focus On Grammar An Course for Reference and Practice. Tp. Hồ Chí Minh: Nxb. Tp. Hồ Chí Minh, 1997.
MLA引用形式Koch, Rachel Spack, , Rachel Spack Koch. Focus On Grammar An Course for Reference and Practice. Tp. Hồ Chí Minh: Nxb. Tp. Hồ Chí Minh, 1997.
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