Malaev, V. G.; Ilyushin, V. A. Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1989 , vol. 38, # 2.2 p. 406 - 407 Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1989 , # 2 p. 462 - 464