1. 1) D. E. Hetzel : Metal Progress, 125(1984)3, p.73
2. 2) C. T. Ward, D. L. Mathis and R. W. Staehle : Corrosion, 25 (1969), p.394
3. 3) G. J. Theus and J. R. Cels : Corrosion Problem in Energy Conversion and Generation, (1974), p.384 [The Electrochemical Society, Princeton, N. J.]
4. 4) G. J. Theus and R. W. Staehle : Stress Corrosion Cracking and Hydrogen Embrittlement of Iron Base Alloys, (1977), p.845 [NACE]
5. 6) M.Takemoto, T.Shinohara and M.Shirai : Materials Performance, 24 (1985), p.26