GOEL, D.; RĂDULESCU, V. D.; SREENADH, K. Variational framework and Lewy-Stampacchia type estimates for nonlocal operators on Heisenberg group. Annales Fennici Mathematici, [S. l.], v. 47, n. 2, p. 707–721, 2022. DOI: 10.54330/afm.116794. Disponível em: https://afm.journal.fi/article/view/116794. Acesso em: 26 may. 2022.