Não informado. (1972). Economic Impact. U.S. Information Agency.
Chicago (17e ed.) BronvermeldingNão informado. Economic Impact. Washington: U.S. Information Agency, 1972.
MLA (8e ed.) BronvermeldingNão informado. Economic Impact. U.S. Information Agency, 1972.
Let op: Deze citaties zijn niet altijd 100% accuraat.