Alexander, L. (1991). New Concept English: Practice and Progress. London: Longman.
Dyfyniad Arddull ChicagoAlexander, L.G. New Concept English: Practice and Progress. London: Longman, 1991.
Dyfyniad MLAAlexander, L.G. New Concept English: Practice and Progress. London: Longman, 1991.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.