Crystal, D. (1997). Cambridge encyclopaedia of language (2nd ed.). Cambridge University Press.
Dyfyniad Arddull ChicagoCrystal, David. Cambridge Encyclopaedia of Language. 2nd ed. Cambridge: Cambridge University Press, 1997.
Dyfyniad MLACrystal, David. Cambridge Encyclopaedia of Language. 2nd ed. Cambridge University Press, 1997.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.