APA-viite

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.

Chicago-tyylinen lähdeviittaus

Koch, Rachel Spack, ja Rachel Spack Koch. Focus On Grammar An Course for Reference and Practice. Tp. Hồ Chí Minh: Nxb. Tp. Hồ Chí Minh, 1997.

MLA-viite

Koch, Rachel Spack, ja 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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