Cita APA (7a ed.)

Gairns R. Ruth & Redman S. Stuart. (2007). Natural English. Pre-intermediate: Student's Book. New York, Oxford University Press, 2007.

Cita Chicago Style (17a ed.)

Gairns R. Ruth y Redman S. Stuart. Natural English. Pre-intermediate: Student's Book. New York, Oxford University Press, 2007, 2007.

Cita MLA (9a ed.)

Gairns R. Ruth y Redman S. Stuart. Natural English. Pre-intermediate: Student's Book. New York, Oxford University Press, 2007, 2007.