Yanovskaya, L. A.; Zhdankina, G. M.; Krystal', G. V.; Serebryakov, E. P. Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1987 , vol. 36, # 12 p. 2587 - 2590 Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1987 , # 12 p. 2790 - 2793