Cita APA

Walker, M., & Avishai, S. (1984). Step ahead: An english course, 1. Reading, Massachusetts : México: Addison-Wesley Pub. Co. Fondo Educativo Interamericano.

Citación estilo Chicago

Walker, Michael, y Susan Avishai. Step Ahead: An English Course, 1. Reading, Massachusetts : México: Addison-Wesley Pub. Co. Fondo Educativo Interamericano, 1984.

Cita MLA

Walker, Michael, y Susan Avishai. Step Ahead: An English Course, 1. Reading, Massachusetts : México: Addison-Wesley Pub. Co. Fondo Educativo Interamericano, 1984.