1. W. Gawlik and G. W. Series, in Proceedings of 4th International Conference on Laser Spectroscopy, Rottach-Egern, Germany, 1979, Ed. by H. Walter and M. Rothe (Springer, Berlin, 1979), Vol. 21, p. 210.
2. D. E. Murnick, M. S. Feld, M. M. Burns, et al., in Proceedings of 4th International Conference on Laser Spectroscopy, Rottach-Egern, Germany, 1979, Ed. by H. Walter and M. Rothe (Springer, Berlin, 1979), Vol. 21, p. 195.
3. I. A. Kartashov and A. V. Shishaev, Pis’ma Zh. Éksp. Teor. Fiz. 58, 501 (1993) [JETP Lett. 58, 502 (1993)].
4. S. G. Rautian and A. V. Shishaev, Zh. Éksp. Teor. Fiz. 108, 807 (1995) [JETP 81, 440 (1995)].
5. I. A. Kartashov, S. G. Rautian, and A. V. Shishaev, in Physics of Vibrations (Allerton, New York, 1998), Vol. 6, p. 143.