Potten, H., & Potten, J. (2001). Clockwise: Elementary classbook [Băng Casset]. Oxford: Oxford University Press.
Chicago Style aipamenaPotten, Heather, và Jonathan Potten. Clockwise: Elementary Classbook [Băng Casset]. Oxford: Oxford University Press, 2001.
MLA aipamenaPotten, Heather, và Jonathan Potten. Clockwise: Elementary Classbook [Băng Casset]. Oxford: Oxford University Press, 2001.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.