Voronkov, M. G.; Basenko, S. V.; Vitkovskii, V. Yu.; Gebel', I. A.; Mirskov, R. G. Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1987 , vol. 36, # 5 p. 1082 - 1084 Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1987 , vol. 36, # 5 p. 1169 - 1171