Safarov, M. G.; Nigmatullin, N. G.; Ibatullin, U. G.; Rafikov,S. R.
Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1982 , vol. 31, # 4 p. 792 - 794
Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1982 , # 4 p. 899 - 902