Extraction of Manganese from Georgia Umber Ore by a Sulfuric Acid-ferrous Sulfate Process (in Two Parts). by Glenn L. Cook, Martin H. Stanczyk, Lanford H. Adami, H. R. Johnson, Joseph M. Pugliese, Wilbur I. Duvall, Ignatz L. Feld, Larry A. Haas, Frederick E. Armstrong, Ronald Barany, Jerry B. F. Champlin, Gilbert M. Farrior, Francis E. Brantley, S. E. Khalafalla, Clifford W. Schultz, Verne E. Hooker, William Joseph Campbell, Dunham James T., J. M. Stuve, Francis X. Tartaron, T. N. Rushton, George Cletus Price, Edward George Davis, C. E. Arthur, Dean W. Boley, Harry R. Nicholls, Herbert P. LeVan, J. L. Eakin, John W. Thatcher, Philip G. Burkhalter, Don R. Thompson, Frank Badda, G. U. Dinneen, L. E. D. Pease, P. G. Barnard, W. E. Eckard, William K. Overbey