Butterman, William C.; Brooks, William E.; Reese, Jr., Robert G. (2004). "Mineral Commodity Profile: Cesium"(PDF). United States Geological Survey. Archived from the original(PDF) on February 7, 2007. பார்க்கப்பட்ட நாள் 2009-12-27.
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Butterman, William C.; Brooks, William E.; Reese, Jr., Robert G. (2004). "Mineral Commodity Profile: Cesium"(PDF). United States Geological Survey. Archived from the original(PDF) on February 7, 2007. பார்க்கப்பட்ட நாள் 2009-12-27.