Davis, E. (1960). Readings for opinion (2nd ed.). Prentice-Hall.
Dyfyniad Arddull ChicagoDavis, Earle. Readings for Opinion. 2nd ed. Englewood clif.: Prentice-Hall, 1960.
Dyfyniad MLADavis, Earle. Readings for Opinion. 2nd ed. Prentice-Hall, 1960.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.