1. E. MEYER,Z. Ver. Dtsch. Ing. 52 (1908) 645.
2. Idem, ibid. 52 (1908) 740.
3. Idem, ibid. 52 (1908) 835.
4. D. TABOR, “The Hardness of Metals” (Oxford University Press, Oxford, 1951).
5. R. HILL, B. STORAKERS and A. B. ZDUNEK, “A Theoretical Study of the Brinell Hardness Test”, Royal Institute of Technology Report TRITA-HFL-0094 (1988) Stockholm, Sweden.