Fattakhov,S.G.; Reznik,V.S. Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1975 , vol. 24, p. 1311 - 1312 Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1975 , vol. 24, # 6 p. 1418 - 1419