CHORNENKA, O. V. Asymptotic analysis of linear systems of differential equations with parameter and regular singular point. Cherkasy University Bulletin: Physical and Mathematical Sciences, [S. l.], v. 389, n. 1, 2017. Disponível em: https://phys-ejournal.cdu.edu.ua/article/view/1381. Acesso em: 17 may. 2026.