PONOMARENKO , A. M. Fractional diffusion equation degenerating on the initial hyperplane. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 73, n. 3, p. 370–380, 2021. DOI: 10.37863/umzh.v73i3.6320. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/6320. Acesso em: 5 dec. 2025.