 | Ibach, D. B. (Donald Bryan), 1900- 4n | (2) |
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 | Ibach, D. B. (Donald Bryan), 1900- 4n; Fertilizer use in the United States : its economic position and outlook / . Washington : Economic Research Service, U.S. Dept. of Agriculture, 1966. | |
| Ibach, D. B. (Donald Bryan), 1900- 4n; Crop yield response to fertilizer in the United States / . Washington, D.C. : U.S. Dept. of Agriculture, Economic Research Service and Statistical Reporting Service, 1968. | |
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