Cherevko, Kateryna, Myroslava Zhyshkovych, Ruslana Kalyn, and Ivanna Komarevych. 2021. “Master Class As a Leading Pedagogical Technology in Professional Improvement of Individual Performing Qualities of Singers”. Amazonia Investiga 10 (47), 282-92. https://doi.org/10.34069/AI/2021.47.11.29.