APA (7e ed.) Bronvermelding

Gairns, R., & Redman, S. (2003). Natural English: Upper-intermediate student's book. Oxford University Press.

Chicago (17e ed.) Bronvermelding

Gairns, Ruth, en Stuart Redman. Natural English: Upper-intermediate Student's Book. Oxford: Oxford University Press, 2003.

MLA (8e ed.) Bronvermelding

Gairns, Ruth, en Stuart Redman. Natural English: Upper-intermediate Student's Book. Oxford University Press, 2003.