AL-SHAIKH, S. B. Riemannian Manifolds Isometric to a Sphere. Contemporary Mathematics , [S. l.], v. 6, n. 4, p. 4687–4696, 2025. DOI: 10.37256/cm.6420257418. Disponível em: https://ojs.wiserpub.com/index.php/CM/article/view/7418. Acesso em: 14 nov. 2026.