Yuvchenko, A. P.; Moiseichuk,K. L.; Dikusar, E. A.; Ol'dekop, Yu. A. Journal of Organic Chemistry USSR (English Translation), 1984 , vol. 20, p. 2298 - 2301 Zhurnal Organicheskoi Khimii, 1984 , vol. 20, # 12 p. 2526 - 2530