SARANEN, J.; WITSCH, K. J. Exterior boundary value problems for elliptic equations. Annales Fennici Mathematici, [S. l.], v. 8, n. 1, p. 3–42, 1983. DOI: 10.5186/aasfm.1983.0821. Disponível em: https://afm.journal.fi/article/view/134455. Acesso em: 25 nov. 2024.