CINTI, Chiara. Sub-solutions and mean-value operators for ultraparabolic equations on Lie groups. MATHEMATICA SCANDINAVICA, [S. l.], v. 101, n. 1, p. 83–103, 2007. DOI: 10.7146/math.scand.a-15033. Disponível em: https://www.mscand.dk/article/view/15033. Acesso em: 6 dec. 2025.