Zubareva, N. D.; Klabunovskii, E. I.; Kheifits, L. A. Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1989 , vol. 38, # 8.2 p. 1765 - 1768 Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1989 , # 8 p. 1920 - 1923