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USA | |
| Jacob, K.D,Hill, W.L,Marshall, H.L,and Reynold D.S.,(1933) The Composition and Distribution of Phosphate Rock with Special Reference to the United States :U.S. Department of Agriculture Technical Bulletion No. 364 |
| Jacob, K.D,Hill, W.L,Marshall, H.L,and Reynold D.S.,(1933) The Composition and Distribution of Phosphate Rock with Special Reference to the United States :U.S. Department of Agriculture Technical Bulletion No. 364 |
| National Geochemical Database :Rocks : USGS File # W195180 |
| Jacob, K.D,Hill, W.L,Marshall, H.L,and Reynold D.S.,(1933) The Composition and Distribution of Phosphate Rock with Special Reference to the United States :U.S. Department of Agriculture Technical Bulletion No. 364 |
| National Geochemical Database : Rocks : USGS File # W195174 -W195174 |
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