Volkov, A. N.; Volkova, K. A.; Levanova, E. P.; Trofimov, B. A.
Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1981 , vol. 30, # 4 p. 612 - 615
Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1981 , # 4 p. 831 - 834