1. A. H. Cottrell, Dislocations and Plastic Flow in Crystals, Oxford, 1953.
2. F. R. N. Nabarro, Phil. Mag.,35, 613, 1977.
3. R. W. Whitworth, Adv. Phys.,24, 203, 1975.
4. A. V. Stepanov, Z. Phys.,81, 560, 1933.
5. V. I. Alshits, M. V. Galustashvili andI. M. Paperno, Kristallografiya,20, 1113, 1975.