Bowler, B., & Cunningham, S. (1991). Headway, Upper-Intermediate: Pronunciation. Oxford: Oxford University Press.
Dyfyniad Arddull ChicagoBowler, Bill, và Sarah Cunningham. Headway, Upper-Intermediate: Pronunciation. Oxford: Oxford University Press, 1991.
Dyfyniad MLABowler, Bill, và Sarah Cunningham. Headway, Upper-Intermediate: Pronunciation. Oxford: Oxford University Press, 1991.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.