FESHCHENKO, S. F.; Shkіl N. I.; Sоtnіchenkо N. A. On asymptotic representation of solutions for a system of linear partial differential equations with time lag. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 23, n. 2, p. 177–189, 1971. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/8500. Acesso em: 6 dec. 2025.