EFTEKHARINASAB, K. A Version of the Hadamard–Lévy Theorem for Fréchet Spaces. Proceedings of the Bulgarian Academy of Sciences, Sofia, Bulgaria, v. 75, n. 8, p. 1099–1104, 2022. DOI: 10.7546/CRABS.2022.08.01. Disponível em: https://proceedings.bas.bg/index.php/cr/article/view/129. Acesso em: 1 oct. 2022.