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2. ASM hand book, vol. 19, Fatigue and Fracture. ASM International, Materials Park, OH 1996, p. 332.
3. Metals hand book, vol. 10, 8th ed. American Society for Metals, Metals Park, Ohio, 1975, p. 98.
4. Metals hand book, vol. 12, 9th ed. 1987, p. 298.
5. Metals hand book, vol. 12. 9th ed. 1987, p. 405.