Dyfyniad APA
Gottheil, F. M. (1996). Principles of economics. South-Western College.
Dyfyniad Arddull Chicago
Gottheil, Fred M. Principles of Economics. Illinois: South-Western College, 1996.
Dyfyniad MLA
Gottheil, Fred M. Principles of Economics. South-Western College, 1996.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.