Varga, M.; Khodonov, A. A.; Mitsner, B. I.; Evstigneeva, R. P. Journal of Organic Chemistry USSR (English Translation), 1987 , vol. 23, # 5 p. 1014 - 1015 Zhurnal Organicheskoi Khimii, 1987 , vol. 23, # 5 p. 1123 - 1125