Roberts, W. H. (1941). The problem of choice: An introduction to ethics. Boston: Atheneum Press.
Dyfyniad Arddull ChicagoRoberts, William Hehry. The Problem of Choice: An Introduction to Ethics. Boston: Atheneum Press, 1941.
Dyfyniad MLARoberts, William Hehry. The Problem of Choice: An Introduction to Ethics. Boston: Atheneum Press, 1941.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.