YURKO, V. A.; BUTERIN, S. A.; PIKULA, M. Sturm-Liouville differential operators with deviating argument. Tamkang Journal of Mathematics, [S. l.], v. 48, n. 1, p. 49–59, 2017. DOI: 10.5556/j.tkjm.48.2017.2264. Disponível em: https://journals.math.tku.edu.tw/index.php/TKJM/article/view/2264. Acesso em: 26 apr. 2024.