%0 Journal Article %A Kh. M. Shadimetov %A R. N. Mirzakabilov %T Optimal difference formulas in the Sobolev space %J Contemporary Mathematics. Fundamental Directions %D 2022 %P 167-177 %V 68 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/item/CMFD_2022_68_1_a12/ %G ru %F CMFD_2022_68_1_a12