OURRAOUI, A. AN EXISTENCE RESULT FOR AN ELLIPTIC PROBLEM INVOLVING A FOURTH ORDER OPERATOR. Journal of Nonlinear Analysis and Optimization: Theory & Applications (JNAO), [S. l.], v. 7, n. 2, p. 51–56, 2018. Disponível em: https://ph03.tci-thaijo.org/index.php/jnao/article/view/2831. Acesso em: 2 sep. 2026.