Postovoi, S. A.; Lantseva, L. T.; Zeifman, Yu. V.; Knunyants, I. L. Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1982 , vol. 31, # 11 p. 2233 - 2236 Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1982 , # 11 p. 2531 - 2535