KOVTONYUK, D.; PETKOV, I.; RYAZANOV, V. I. On the regular solutions of the Dirichlet problem for Beltrami equations . Reports of the National Academy of Sciences of Ukraine, Kyiv, Ukraine, n. 3, p. 13–17, 2014. DOI: 10.15407/dopovidi2014.03.013. Disponível em: https://nasu-periodicals.org.ua/index.php/dp/article/view/15601. Acesso em: 20 jun. 2026.