Trifonova, V.N.; Zorin, V.V.; Zlot-skii, S.S.; Rakhmankulov, D.L. Journal of Organic Chemistry USSR (English Translation), 1982 , vol. 18, p. 909 - 912 Zhurnal Organicheskoi Khimii, 1982 , vol. 18, # 5 p. 1050 - 1053