Hofferbert, R. I. (1974). The study of public policy. Bobbs-Merrill.
Dyfyniad Arddull ChicagoHofferbert, Richard I. The Study of Public Policy. New York: Bobbs-Merrill, 1974.
Dyfyniad MLAHofferbert, Richard I. The Study of Public Policy. Bobbs-Merrill, 1974.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.