JAFAROV, Sadulla Z. Best trigonometric approximation and modulus of smoothness of functions in weighted grand Lebesgue spaces. Bulletin of the Karaganda University. Mathematics Series, [S. l.], v. 94, n. 2, p. 26–32, 2019. Disponível em: http://mts.buketov.edu.kz/index.php/mathematics-vestnik/article/view/266. Acesso em: 3 oct. 2025.