IRGASHEV, B. Yu. On partial solutions of one equation with multiple characteristics and some properties of the fundamental solution. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 68, n. 6, p. 763–787, 2016. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/1877. Acesso em: 5 dec. 2025.