1. G. A. Zlobina and V. V. Ershov, Izv. Akad. Nauk SSSR, Ser. Khim.,1964, 1666.
2. A. A. Volod'kin and V. V. Ershov, Izv. Akad. Nauk SSSR, Otd. Khim. Nauk,1962, 2022.
3. E. Ziegler and G. Snatzke, Monatsh. Chem.,84, 271 (1953).
4. E. Grandmougin and H. Freimann, Chem. Ber.,40, 3453 (1907).
5. I. S. Ioffe, Zh. Obshch. Khim.,7, 2637 (1937).