MALYTSKA, H.P.; BURTNYAK, I.V. Method of parametrix for the ultraparabolic systems. Carpathian Mathematical Publications, [S. l.], v. 2, n. 2, p. 74–82, 2010. Disponível em: https://scijournals.pnu.edu.ua/index.php/cmp/article/view/3968. Acesso em: 20 apr. 2024.