ARIF, Muhammad Shoaib; ER-CHUAN, Zhang; HUA-FEI, Sun. JACOBI FIELDS ON THE MANIFOLD OF FREUND. Italian Journal of Pure and Applied Mathematics, [S. l.], v. 34, p. 181–188, 2015. Disponível em: https://journals.uniurb.it/index.php/ijpam/article/view/6343. Acesso em: 7 aug. 2026.