Cita APA

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.

Citación estilo Chicago

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

Cita MLA

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