Frankel, I., & Irene Frankel. (1998). Gateways: Integrated english. New York, NY, USA: Oxford University Press.
Chicago Style aipamenaFrankel, Irene, và Irene Frankel. Gateways: Integrated English. New York, NY, USA: Oxford University Press, 1998.
MLA aipamenaFrankel, Irene, và Irene Frankel. Gateways: Integrated English. New York, NY, USA: Oxford University Press, 1998.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.