The Existence of Three Positive Solutions for $p$-Laplacian Difference Equation with Delay. Communications in Mathematical Research, [S. l.], v. 28, n. 4, p. 337–348, 2021. Disponível em: https://www.global-sci.com/index.php/cmr/article/view/8746. Acesso em: 6 dec. 2025.