North Dakota Agricultural College. Agricultural Extension Division. (1918). Circular. Agricultural Extension Division, North Dakota Agricultural College.
Chicago-viite (17. p.)North Dakota Agricultural College. Agricultural Extension Division. Circular. Fargo, N.D.: Agricultural Extension Division, North Dakota Agricultural College, 1918.
MLA-viite (8. p.)North Dakota Agricultural College. Agricultural Extension Division. Circular. Agricultural Extension Division, North Dakota Agricultural College, 1918.
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