Zhiryukhina, N. P.; Galkina, M. A.; Chukovskaya, E. Ts. Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1983 , vol. 32, p. 1294 - 1296 Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1983 , # 6 p. 1426 - 1428