Não informado. (1984). Current farm economics. Oklahoma Agricultural Experiment Station.
Chicago (17e ed.) BronvermeldingNão informado. Current Farm Economics. Stillwater, Okla: Oklahoma Agricultural Experiment Station, 1984.
MLA (8e ed.) BronvermeldingNão informado. Current Farm Economics. Oklahoma Agricultural Experiment Station, 1984.
Let op: Deze citaties zijn niet altijd 100% accuraat.