Não informado. (1938). Bimonthly Bulletin of the North Dakota Agricultural Experiment Station. North Dakota Agricultural Experiment Station.
Citação do estilo Chicago (17ª ed.)Não informado. Bimonthly Bulletin of the North Dakota Agricultural Experiment Station. Fargo, ND: North Dakota Agricultural Experiment Station, 1938.
Citação MLA (8ª ed.)Não informado. Bimonthly Bulletin of the North Dakota Agricultural Experiment Station. North Dakota Agricultural Experiment Station, 1938.
Atenció: Aquestes cites poden no estar 100% correctes.