Ogorodnikova, N. A.; Kvasov, B. A.; Kravtsov, D. N. Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1988 , vol. 37, # 6 p. 1268 - 1270 Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1988 , # 6 p. 1434 - 1436