SOLÓRZANO, Newton Mayer; LOPEZ, Edwin; SOUZA, Marcelo Almeida de. On spherically Symmetric Douglas metrics with vanishing S-curvature with explicit examples. NEXUS Mathematicæ, Goiânia, v. 2, 2019. Disponível em: https://revistas.ufg.br/nexus/article/view/56023. Acesso em: 5 dez. 2025.