1. Kovalenko S.M., Gusarov V.I., Zaremba O.V., Zubar V.V. Synthesis and spectral properties of 1,3,4-oxadiazol-2-yl-coumarines containing 3,7,12-threehydroxycholic fragment // V. N. Karazin Kharkiv National University Bulletin. Chemical series. 2015. № 25. C. 46-53.