1. 1) K.E. PUTTICK: JISI, 185 (1957), p.161
2. 2) B.R. BUTCHER and H.R. PETTIT: JISI, 204 (1966), p.469
3. 3) D.P. CLAUSING: Trans. ASM, 60 (1967), p.504
4. 4) L.E. MILLER and G.C. SMITH: JISI, 208 (1970), p.998
5. 5) C.F. TIPPER: Metallurgia, 39 (1949), p.133