1. Proc. Europ. Conf. Voids Formed by Irradiation of Reactor Materials (edit. by Pugh, S. F., Loretto, M. H., and Norris, D. I. R.) (Brit. Nucl. Energy Soc., 1971).
2. Proc. Intern. Conf. Radiation Induced Voids in Metals, SUNY, Albany, New York, June 1971 (to be published).
3. Ashby, M. F., and Brown, L. M., Phil. Mag., 8, 1649 (1963).
4. Powell, R. W., and Russell, K. C., Radiat. Effects, 12, 127 (1972).