1. P. S. Symonds, T. C. T. Ting and D. N. Robinson, Div. of Engng, Brown University, Providence, R. I., 1967.
2. T. Nicholas, inImpact Dynamics. Edited by J. A. Zukas et al, John Wiley, New York 1982.
3. T. Karman von and P. Duwez, J. Appl. Mech.21, 987?994 (1950).
4. L. E. Malvern, J. Appl. Mech.22, 203?208 (1951).
5. S. R. Bodner and J. Aboudi, Int. J. Solids Structures.19, 305?314 (1983).