AFROUZI, G. A.; RASOULI, S. H. On Positive Solutions for Some Nonlinear Semipositone Elliptic Boundary Value. Nonlinear Analysis: Modelling and Control, [S. l.], v. 11, n. 4, p. 323–329, 2006. DOI: 10.15388/NA.2006.11.4.14736. Disponível em: https://www.journals.vu.lt/nonlinear-analysis/article/view/14736.. Acesso em: 7 may. 2024.