PICHUGOV, S. A. Asymptotic behavior of the best approximations for the functions in $L_p$. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 45, n. 6, p. 867–870, 1993. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/5876. Acesso em: 5 dec. 2025.