1. A. I. Deeming and B. L. Shaw, J. Chem. Soc. A, No. 1, 1887 (1967).
2. Yu. S. Varshavskii and T. G. Cherkasova, Zh. Neorg. Khim.,12, No. 3, 107 (1967).
3. J. T. Mague, Inorg. Chem.,11, No. 6, 2558–2564 (1972).
4. É. N. Yurchenko, Kinet. Katal.,14, No. 1, 515–516 (1973).
5. É. N. Yurchenko, A. D. Troitskaya, L. S. Gracheva, and L. Ya. Al't, Izv. Akad. Nauk SSSR, Ser. Khim., No. 10, 2153–2156 (1975).