Ermilova, M. M.; Orekhova, N. V.; Skakunova, E. V.; Gryaznov, V. M. Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1988 , vol. 37, p. 637 - 640 Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1988 , # 4 p. 750 - 755