Authors
V. S. Shpakivskyi
Department of complex analysis and potential theory, Institute of Mathematics of the National Academy of Science of Ukraine, 3 Tereshchenkivs'ka Street,, Kyiv, Ukraine
T. S. Kuzmenko
Department of complex analysis and potential theory, Institute of Mathematics of the National Academy of Science of Ukraine, 3 Tereshchenkivs'ka Street,, Kyiv, Ukraine