MATYCHUK, M. I. Nonlocal parabolic boundary-value problem. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 48, n. 3, p. 362–367, 1996. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/5333. Acesso em: 5 dec. 2025.