Asymptotic solutions to the first order differential equation with deviated argument and slowly varying coefficients. Neliniini Kolyvannya, [S. l.], v. 7, n. 4, p. 475–486, 2004. Disponível em: https://twinhead.imath.kiev.ua/index.php/nosc/article/view/324. Acesso em: 22 jan. 2026.