RAMM, Alexander G. A short proof of the existence of the solution to elliptic boundary problem. Global Journal of Mathematical Analysis, [S. l.], v. 3, n. 3, p. 105–108, 2015. DOI: 10.14419/gjma.v3i3.4731. Disponível em: https://sciencepubco.com/index.php/GJMA/article/view/4731.. Acesso em: 2 may. 2024.