Columbia law review, Volume 91, Nos 4-6, 1991. The Columbia University Press.
Dyfyniad Arddull ChicagoColumbia Law Review, Volume 91, Nos 4-6, 1991. New York: The Columbia University Press.
Dyfyniad MLAColumbia Law Review, Volume 91, Nos 4-6, 1991. The Columbia University Press.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.