Sokolova, E. A.; Maretina, I. A.; Petrov, A. A. Journal of Organic Chemistry USSR (English Translation), 1984 , vol. 20, # 8 p. 1500 - 1505 Zhurnal Organicheskoi Khimii, 1984 , vol. 20, # 8 p. 1648 - 1653