Markovskii,V.I. et al.
Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1975 , vol. 24, # 12 p. 2730 - 2731
Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1975 , vol. 24, # 12 p. 2838 - 2840

Shcherbakov,V.I. et al.
Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1976 , vol. 25, # 12 p. 2620 - 2621
Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1976 , vol. 25, # 12 p. 2811 - 2812