ZAKORA, D. A. Abstract Linear Volterra Second-Order Integro-Differential Equations. Eurasian Mathematical Journal, [S. l.], v. 7, n. 2, p. 75–91, 2016. Disponível em: https://emj.enu.kz/index.php/main/article/view/636. Acesso em: 31 oct. 2025.