Grigor'ev, N. A.; Kuz'mina, N. A.; Chukovskaya, E. Ts.; Tumanskaya, A. L.; Freidlina, R. Kh. Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1980 , vol. 29, # 6 p. 952 - 955 Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1980 , # 6 p. 1333 - 1336