Cheskis, B. A.; Shpiro, N. A.; Moiseenkov, A. M. Journal of Organic Chemistry USSR (English Translation), 1990 , vol. 26, # 9.1 p. 1613 - 1616 Zhurnal Organicheskoi Khimii, 1990 , vol. 26, # 9 p. 1864 - 1869