Orlinkov, A. V.; Akhrem, I. S.; Afanas'eva, L. V.; Vitt, S. V.; Vol'pin, M. E. Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1991 , vol. 40, # 1.1 p. 90 - 92 Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1991 , # 1 p. 105 - 108