RomanyukA. S. and RomanyukV. S. (2012) “Best bilinear approximations of functions from Nikolskii-Besov classes”, Ukrains’kyi Matematychnyi Zhurnal, 64(5), pp. 685-697. Available at: https://umj.imath.kiev.ua/index.php/umj/article/view/2608 (Accessed: 24November2024).