Positive Periodic Solutions for First-Order Nonlinear Neutral Differential Equations. Journal of Nonlinear Modeling and Analysis, [S. l.], v. 7, n. 3, p. 938–945, 2025. DOI: 10.12150/jnma.2025.938. Disponível em: https://www.global-sci.com/index.php/jnma/article/view/13840. Acesso em: 5 dec. 2025.