Ogibin,Yu.N. et al.
Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1975 , vol. 24, p. 1241 - 1247
Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1975 , vol. 24, # 6 p. 1345 - 1352