EL-NABULSI, R. A.; REZAZADEH, H. NON-STANDARD LAGRANGIANS WITH DIFFERENTIALS OPERATORS. Journal of Nonlinear Analysis and Optimization: Theory & Applications (JNAO), [S. l.], v. 5, n. 2, p. 21–35, 2013. Disponível em: https://ph03.tci-thaijo.org/index.php/jnao/article/view/2747. Acesso em: 2 sep. 2026.