1. H.J. Wiester, H.A. Vogels, and H. Ulmer: Stahl Eisen, 1959, vol. 79, pp. 1120–29.
2. W.B. Morrison: J. Iron Steel Inst., 1963, vol. 201, pp. 317–25.
3. D. Webster and J. H. Woodhead: J. Iron Steel Inst., 1964, vol. 202, pp. 987–94.
4. K.J. Irvine and F.B. Pickering: J. Iron Steel Inst., 1963, vol. 201, pp. 944–60.
5. K.J. Irvine, F.B. Pickering, and T. Gladman: J. Iron Steel Inst., 1967, vol. 205, pp. 161–82.