ZELINSKII, Yu. B. Helly Theorem and Related Results. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 54, n. 1, p. 125–128, 2002. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/4045. Acesso em: 27 apr. 2025.