APA (7. basım) Alıntı

Iowa. State Planning Board. Soil Conservation Committee. (1938). Soil conservation districts for Iowa? Iowa State Planning Board.

Chicago Style (17. basım) Atıf

Iowa. State Planning Board. Soil Conservation Committee. Soil Conservation Districts for Iowa? [Des Moines]: Iowa State Planning Board, 1938.

MLA (8th ed.) Atıf

Iowa. State Planning Board. Soil Conservation Committee. Soil Conservation Districts for Iowa? Iowa State Planning Board, 1938.