Molchanov, L. V.; Ayupova, A. T.; Kadyrov, Ch. Sh.; Shapkin, V. A. Chemistry of Natural Compounds, 1983 , vol. 19, # 3 p. 196 - 198 Khimiya Prirodnykh Soedinenii, 1983 , vol. 19, # 3 p. 207 - 209