Group Classification of Second-Order Linear Neutral Differential Equations. Contemporary Mathematics , [S. l.], v. 5, n. 2, p. 2376–2396, 2024. DOI: 10.37256/cm.5220243221. Disponível em: https://ojs353.mebyme.cn/index.php/CM/article/view/3221. Acesso em: 24 dec. 2025.