Princeton Language Institute. (1993). 21st century spelling dictionary. Dell Pub.
Dyfyniad Arddull ChicagoPrinceton Language Institute. 21st Century Spelling Dictionary. New York: Dell Pub, 1993.
Dyfyniad MLAPrinceton Language Institute. 21st Century Spelling Dictionary. Dell Pub, 1993.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.