1. D.M.S. Report No. 23, Dept. Mater. Sci., Stanford University, 1964.
2. and , Hot Workability Testing Techniques, Metal Forming, Ed. Plenum Press, New York 1971 (p. 393).
3. , and , Iron and Steel Inst. (London) Publ. No. 108 (1968).
4. and , see [4] (p. 68).