1. 1) M. L. BECKER, C. E. PHILLIPS: J. Iron and Steel Inst.(U. K.), 133 (1936), p.427
2. 2) L. S. COPE: Trans. Amer. Soc. Steel Treating, 14 (1928), p.51
3. 3) O. V. GREENE Trans. Amer. Soc. Steel Treating, 18 (1930). p.369
4. 5) R. G. TREUTING et ali: Residual Stress Measurements (Amer. Soc. Metals, 1952), p.42
5. 6) K. HEINDLHOFER: Evaluation of Residual Stress (McGraw-Hill, 1948), p.113