1. L. L. Kimtis, Molecular Spectroscopy [in Russian], No. 6, Leningrad (1983), pp. 216?226.
2. Sh. A. Markar'yan, V. S. Davtyan, and N. M. Beileryan, Armen. Khim. Zh., 34, No. 6, 343?348 (1984).
3. V. M. Staroverov, é. S. Shcherbakova, V. I. Popovich, and A. F. Abramov, Zh. Prikl. Spektrosk.,45, No. 2, 288?293 (1986).
4. V. M. Zakoshanskii, A. M. Dobrotvorskii, V. V. Pizhon, and V. P. Chulkov, Zh. Obshch. Khim.,56, No. 3, 665?670 (1986).
5. P. Ruostesio and T. Mattila, Thermochim. Acta,104, 153?158 (1986).