Clark, C. (1957). The conditions of economic progress (3rd ed.). New York: St. Martins Pr..
Chicago (17e ed.) BronvermeldingClark, Colin. The Conditions of Economic Progress. 3rd ed. London: Macmillan: New York: St. Martins Pr., 1957.
MLA (9e ed.) BronvermeldingClark, Colin. The Conditions of Economic Progress. 3rd ed. New York: St. Martins Pr., 1957.
Let op: Deze citaties zijn niet altijd 100% accuraat.