1. L.M. Hogan and G. L. F. Powell:J. Austral. Inst. Metals, 1966, vol. 11, p. 235.
2. A. Walton:International Science and Technology, Dec. 1966, p. 28.
3. K. A. Jackson,Ind. Eng. Chem., 1965, vol. 57, p. 28.
4. G. A. Chadwick:Metals and Materials, 1969, vol. 3, no. 3, p. 77.
5. B. E. Sundquist and L.F. Mondolfo:Trans. TMS-AIME, 1961, vol. 221, p. 607.