MARTIO, O. Reflection principle for solutions of elliptic partial differential equations and quasiregular mappings. Annales Fennici Mathematici, [S. l.], v. 6, n. 1, p. 179–187, 1981. DOI: 10.5186/aasfm.1981.0610. Disponível em: https://afm.journal.fi/article/view/134409. Acesso em: 25 nov. 2024.