The Second-Order Melnikov Function and Chaotic Tangles on Toral van der Pol Equation. Journal of Nonlinear Modeling and Analysis, [S. l.], v. 7, n. 6, p. 2001–2012, 2025. DOI: 10.12150/jnma.2025.2001. Disponível em: https://www.global-sci.com/index.php/jnma/article/view/23342. Acesso em: 5 dec. 2025.