1. L. Bellamy, Infrared Spectra of Complex Molecules, 2nd ed. Wiley, New York (1958).
2. Z. P. Pakudina and A. S. Sadykov, The Distribution in Plants and the Physicochemical Properties of Flavones, Flavonols, and Their Glycosides [in Russian], Tashkent (1970).
3. T. A. Geissmann, The Chemistry of Flavonoid Compounds, Pergamon, Oxford (1962).
4. V. I. Litvinenko and N. P. Maksyutina, Khim. Prir. Soedin., 420 (1965).
5. S. Z. Ivanova, G. G. Zapesochnaya, V. I. Sheichenko, S. A. Medvedeva, and N. A. Tyukavkina, Khim. Prir. Soedin., 196 (1978).