BLATT, H. P.; GROTHMANN, R.; KOVACHEVA, R. K. Sign changes in rational Lw1-approximation. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 58, n. 2, p. 283–287, 2006. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/3452. Acesso em: 6 dec. 2025.