Existence Results for Neutral and Second-Order Functional Differential Equations with Causal Operators in $L^p_{\mathrm{loc}}$ Spaces. European Journal of Pure and Applied Mathematics, Maryland, USA, v. 19, n. 1, p. 7151, 2026. DOI: 10.29020/nybg.ejpam.v19i1.7151. Disponível em: https://www.ejpam.com/index.php/ejpam/article/view/7151. Acesso em: 17 feb. 2026.