Radley, P. (2005). Horizons: Student's book 1. Oxford: Oxford University Press.
Dyfyniad Arddull ChicagoRadley, Paul. Horizons: Student's Book 1. Oxford: Oxford University Press, 2005.
Dyfyniad MLARadley, Paul. Horizons: Student's Book 1. Oxford: Oxford University Press, 2005.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.