1. S. P. Keeler: Paper No. 680092, Presented at the SAE Congress, Detroit, January 1968.
2. G. M. Goodwin: Paper No. 680093, Presented at the SAE Congress, Detroit, January 1968.
3. S. S. HeckenProc. 7th Biennial Congress of IDDRG, p. 5.1, Amsterdam, October 1972.
4. A. K. Ghosh and W. A. Backofen:Met. Trans., 1973, vol. 4, p. 113.
5. T. Kobayashi, H. Ishigaki, and T. Abe:Proc. 7th Biennial Congress of IDDRG, p. 8.1, Amsterdam, October 1972.