Volkov, Yu. P.; Kalinevich, V. M.; Trusova, E. I.; Bilevich, K. A.; Kryshtal', G. V.; Yanovskaya, L. Ya. Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1986 , vol. 35, # 6 p. 1239 - 1242 Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1986 , # 6 p. 1365 - 1368