1. Cocks, M., Nature, 170, 203 (1952); Proc. Phys. Soc., 67, 238 (1954).
2. Kerridge, M., “Radioisotope Techniques”, 2, 26 (H.M.S.O., London, 1951).
3. Timoshenko, S., “Theory of Elasticity”, 337 et seq. (McGraw-Hill, New York, 1934).
4. Poritsky, H., J. App. Mech., 17, 191 (1950).
5. McFarlane, J. S., and Tabor, D., Proc. Roy. Soc., A, 202, 224 (1950).