Cita APA

Bolton, D., Oxenden, C., & Peterson, L. (1989). Oxford intensive english courses. OK student's book. Oxford: Oxford University Press.

Citación estilo Chicago

Bolton, David, Clive Oxenden, y Len Peterson. Oxford Intensive English Courses. OK Student's Book. Oxford: Oxford University Press, 1989.

Cita MLA

Bolton, David, Clive Oxenden, y Len Peterson. Oxford Intensive English Courses. OK Student's Book. Oxford: Oxford University Press, 1989.