, D. V. R. D. S. Periodic Solutions Averaging Methods in Nonlinear Ordinary Differential Equations. International Journal on Future Revolution in Computer Science & Communication Engineering, [S. l.], v. 4, n. 7, p. 23–30, 2018. Disponível em: http://www.ijfrcsce.org/index.php/ijfrcsce/article/view/1700. Acesso em: 7 may. 2024.