1. Paper presented at the Conference on the Uses of Large Radiation Sources in Industry, CW/IIA/31;Ohnishi,1959
2. Piette, L. H. Private communication
3. Paper presented at the 14th Annual Meeting of the Japan Physical Society;Koga,1959
4. Powell, R. S., Lawton, E. J. and Balwit, G. S. Paper presented at the 1959 Spring Meeting of the American Physical Society
5. Ohnishi, S.et al. To be published