Potatov, V. M.; Dem'yanovich, V. M.; Vendrova, O. E.; Strel'tsova, E. S. Journal of Organic Chemistry USSR (English Translation), 1981 , vol. 17, # 11 p. 2080 - 2083 Zhurnal Organicheskoi Khimii, 1981 , vol. 17, # 11 p. 2329 - 2333