Lange, O. (1963). Political economy. New York: The MacMillan Company.
Dyfyniad Arddull ChicagoLange, Oskar. Political Economy. New York: The MacMillan Company, 1963.
Dyfyniad MLALange, Oskar. Political Economy. New York: The MacMillan Company, 1963.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.