Gairns, R., & Redman, S. (2006). Natural English: Pre-intermediate student's book. Oxford University Press.
Čikaški stil citiranja (17. izdanje)Gairns, Ruth, i Stuart Redman. Natural English: Pre-intermediate Student's Book. Oxford: Oxford University Press, 2006.
MLA način citiranja (8. izdanje)Gairns, Ruth, i Stuart Redman. Natural English: Pre-intermediate Student's Book. Oxford University Press, 2006.
Upozorenje: Ovi citati možda nisu uvijek 100% točni.