UI/UX design of educational on-line courses. - Kateryna V. Vlasenko; Iryna V. Lovianova; Sergii V. Volkov; Iryna V. Sitak; Olena O. Chumak; Andrii V. Krasnoshchok; Nataliia G. Bohdanova; Serhiy O. Semerikov (CTE, 2021)