BELTAGY, M. Crosscuts in sphere. Tamkang Journal of Mathematics, [S. l.], v. 36, n. 4, p. 275–278, 2005. DOI: 10.5556/j.tkjm.36.2005.99. Disponível em: https://journals.math.tku.edu.tw/index.php/TKJM/article/view/99. Acesso em: 26 apr. 2024.