EXISTENCE OF SOLUTIONS TO SOME BOUNDARY VALUE PROBLEMS WITH ϕ-LAPLACIAN OPERATORS USING MULTIPLE SIGN CONDITIONS. Far East Journal of Mathematical Sciences (FJMS), [S. l.], v. 143, n. 1, p. 261–278, 2025. DOI: 10.17654/0972087126016. Disponível em: https://pphmjopenaccess.com/fejms/article/view/3643. Acesso em: 5 jan. 2026.