, . . English summaries. Butlletí de la Societat Catalana de Matemàtiques, [S. l.], v. 31, n. 2, p. 195–196, 2017. Disponível em: https://revistes.iec.cat/index.php/BSCM/article/view/93712.001. Acesso em: 2 may. 2024.