1. K. Drexhage, Dye Lasers [Russian translation], Moscow (1976), p. 204.
2. D. Basting, D. Ouw, and F. P. Schäfer, Opt. Commun.,18, No. 3, 260?262 (1976).
3. V. I. Alekseeva et al., Abstracts of Reports at the 2nd All-Union Conference on Lasers Based on Complex Organic Compounds and Their Applications, Minsk (1977), pp. 49?51.
4. V. I. Studenov, V. S. Smirnov, and K. P. Korostelev, Opt. Spektrosk.,56, No. 4, 637?642 (1984).
5. F. Kehrmann, Ber.40, 2071 (1907).