Koenig, C. L., & Oxenden, C. (2013). American English file: Teacher's book. Oxford: Oxford University Press.
Dyfyniad Arddull ChicagoKoenig, Chistina Latham, và Clive Oxenden. American English File: Teacher's Book. Oxford: Oxford University Press, 2013.
Dyfyniad MLAKoenig, Chistina Latham, và Clive Oxenden. American English File: Teacher's Book. Oxford: Oxford University Press, 2013.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.