Dyfyniad APA

Koenig, C. L., Oxenden, C., & Boyle, M. (2013). American English file: Workbook. Oxford: Oxford University Press.

Dyfyniad Arddull Chicago

Koenig, Chistina Latham, Clive Oxenden, và Mike Boyle. American English File: Workbook. Oxford: Oxford University Press, 2013.

Dyfyniad MLA

Koenig, Chistina Latham, Clive Oxenden, và Mike Boyle. American English File: Workbook. Oxford: Oxford University Press, 2013.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.