Keiko, N. A.; Rulev, A. Yu.; Kalikhman, I. D.; Voronkov, M. G. Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1985 , vol. 34, # 11 p. 2419 - 2421 Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1985 , # 11 p. 2610 - 2612