USTINSKOVS, Jevgeņijs. Kinds of Improvisation Activity in Music Secondary Schools. SOCIETY. INTEGRATION. EDUCATION. Proceedings of the International Scientific Conference, Rezekne, Latvia, v. 1, p. 163–171, 2015. DOI: 10.17770/sie2012vol1.32. Disponível em: https://journals.rta.lv/index.php/SIE/article/view/32.. Acesso em: 4 may. 2024.