1. 1) T. S. Calayag: Mining Eng., 35 (1983), 727.
2. 2) W. Mihaichuk: Machine Design, 53 (1981), 133.
3. 3) D. Apelian, M. Paliwal and D. C. Herrshaft: J. Met., 33 (1981), 12.
4. 4) E. J. Kubel Jr.: Adv. Mater. Process., 132 (1987), 51.
5. 5) Engineering Properties of Zinc Alloys, 3rd edition, ed. by F. E. Goodwin and A. L. Ponikvay, ILZRO, New York, USA, (1988), p. 1.