1. L.W. Garrett, “Process for the Production of Sulfates” (U.S. patent 4,337,228, 29 June 1982).
2. J.A. Huckabay, “Method for Treatment of Aluminum Dross Oxides” (U.S. patent 4,434,142, 24 February 1984).
3. D.A. Huckabay and A.D. Skiathas, “Aluminum Dross Processing” (U.S. patent 4,252,776, 28 February 1984).
4. A. Durward and D.S. Arthur, “Aluminum Sulfate Manufacture from Aluminum Dross Tailings” (U.S. patent 4,320,098, 16 March 1982).
5. American Encyclopedia, vol. 1 (Grolier Enterprise, 1988), p. 640.