1. E. N. Severin, Zh. Prikl. Spektr.,11, No. 2 (1969).
2. K. Miz, Theory of the Photographic Process [in Russian], Gostekhizdat, Moscow-Leningrad (1949), p. 180.
3. K. V. Chibisov, Theory of Photographic Processes [in Russian], Kinofotoizdat, Moscow (1935), p. 140.
4. E. N. Severin, Zh. Prikl. Spektr.,7, 910 (1967).
5. J. H. Webb and C. H. Evans, JOSA,28, 431 (1938).