Bakibaev, A. A.; Savchenko, T. I.; Filimonov, V. D.; Yagovkin, A. Yu.; Novikov, A. N. Journal of Organic Chemistry USSR (English Translation), 1988 , vol. 24, # 12 p. 2331 - 2334 Zhurnal Organicheskoi Khimii, 1988 , vol. 24, # 12 p. 2581 - 2584