Cita APA (7th ed.)

Bonner, M. (1994). Focus on grammar. Teacher's manual. An intermediate course for reference and practice. Addison-Wesley.

Cita Chicago (17th ed.)

Bonner, Margaret. Focus on Grammar. Teacher's Manual. An Intermediate Course for Reference and Practice. Reading: Addison-Wesley, 1994.

Cita MLA (9th ed.)

Bonner, Margaret. Focus on Grammar. Teacher's Manual. An Intermediate Course for Reference and Practice. Addison-Wesley, 1994.