1. Metals Handbook, 8th ed., ASM, Metals Park, OH, 1964, vol. 2, pp. 1–3.
2. K.E. Thelning: Steel and Its Heat Treatment, Butterworth and Co., London, 1975, pp. 177–81.
3. W. Hewitt: Heat Treatment Met., 1982–83, pp. 56–62.
4. L.E. Heron: Metallurgia, 1969, vol. 80 (478), pp. 53–58.
5. Heat Treater’s Guide, 2nd ed, ASM INTERNATIONAL, Materials Park, OH, 1995, p. 429.