Não informado. (1960). Oklahoma current farm economics. Oklahoma Agricultural Experiment Station.
Chicago-Zitierstil (17. Ausg.)Não informado. Oklahoma Current Farm Economics. Stillwater, Okla: Oklahoma Agricultural Experiment Station, 1960.
MLA-Zitierstil (8. Ausg.)Não informado. Oklahoma Current Farm Economics. Oklahoma Agricultural Experiment Station, 1960.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.