Akhrem, I. S.; Chistovalova, N. M.; Malysheva, A. V.; Vol'pin, M. E. Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1983 , vol. 32, # 12 p. 2417 - 2422 Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1983 , # 12 p. 2696 - 2702