PREDNASAJUCI / LECTURER : Dr. E.P. Pavlenko, Crimean Astrophysical Observatory, Ukraine NAZOV / TITLE : The sources of a “dark matter” in cataclysmic variables ABSTRAKT / ABSTRACT : Cataclysmic variables (CVs) represent significant part of baryon matter in our Galaxy according to the modern X-ray data. CVs are intrinsically very faint close binaries and are unknown objects until they manifest themselves via bright outburst. Study of CVs allows us to investigate the late stage of the stellar evolution, partially, it is of great importance for cosmology. From this point of view the review of some discoveries and findings in the field of CVs based on the observations carried out in the Crimean Astrophysical Observatory, Stara Lesna Observatory and Terskol Observatory, is done.