GUTLYANSKY , V. Ya.; RYAZANOV , V. I. Solutions with peculiarities of one equation of mathematical physics. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 44, n. 2, p. 174–178, 1992. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/7829. Acesso em: 6 dec. 2025.