AKOBIRSHOEV, M. O.; SHABOZOV, M. Sh. On exact values of quasiwidths for some classes of differentiable periodic functions of two variables. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 61, n. 6, p. 855–864, 2009. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/3063. Acesso em: 11 apr. 2025.