1. A. Arrak, Applied Spectroscopy,16, 4, 124 (1962).
2. M. Slavin, Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy (1960).
3. E. N. Severin, Author's Abstract of Ph.D. Dissertation [in Russianl, Dnepropetrovsk (1971).
4. S. A. Shipitsyn, Reports of the 10th Conference on Spectroscopy [in Russian], Izd. Gosuniversiteta, L'vov (1958).
5. K. Miz, Theory of the Photographic Process [Russian translation], Izd. Tekhniko-Teor. Lit., Moscow (1949).