1. S.L. Case and K.R. Van Horn, Aluminum in Iron and Steel (New York: Wiley, 1953), p. 4.
2. R.A. Hadfield, U.S. patent 422,403 (1897).
3. R.A. Hadfield, Trans. Am. Inst. Min. Eng. 19, 1041 (1891).
4. F.R. Morral, J. Iron Steel Inst. 130, 419 (1934).
5. L.J. Huetter and H.H. Stadelmeier, Acta Metall. 6, 367 (1958).