1. R. PELTIER, RILEM Bull. 19 (1954) 29.
2. P. J. F. WRIGHT, Mag. Conc. Res. (London) 7 (20) (1955) 87.
3. O. G. INGLES and S. FRYDMAN, Proceedings of the 4th Australia-New Zealand Conference on Soil Mechanics and Foundation Engineering, Adelaide (University of Adelaide, Adelaide 1963) 213–19.
4. P. S. B. COLBACK, Proceedings of the First Congress of the International Society of Rock Mechanics, Lisbon, Vol. 1 (Laboratorie Nacionale de Engenharia Civil, Lisbon, 1966) pp. 385–91.
5. V. RAMAKRISHNAN, Y. ANANTHANARAYANA and K. C. GOPAL, Indian Conc. J. 41 (1967) 202.