MURACH, A. A. On elliptic systems in Hörmander spaces. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 61, n. 3, p. 391–399, 2009. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/3027. Acesso em: 5 dec. 2025.