1. Jahoda, F. C., Little, E. M., Quinn, W. E., Sawyer, G. A., and Stratton, T. F., Phys. Rev., 119, 843 (1960).
2. McWhirter, R. W. P., Bull. Amer. Phys. Soc., 8, 164 (1963).
3. Cunningham, S. P., U.S. Atomic Energy Comm. Rep. WASH-289 (1955).
4. Williams, R. V., and Kaufman, S., Proc. Phys. Soc., 75, 329 (1960).
5. Thonemann, P. C., Optical Spectrometric Measurements of High Temperatures, ed. by Dickerman, W., 56 (University of Chicago Press, Chicago, 1961).