Petrova,R.G.; Freidlina,R.Kh. Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1975 , vol. 24, p. 1686 - 1689 Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1975 , vol. 24, # 8 p. 1805 - 1808