%0 Journal Article %A Kh. P. Rustamov %T Equivalence of $K$-functional and modulus of smoothness of functions on the sphere %J Matematičeskie zametki %D 1992 %P 123-129 %V 52 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/MZM_1992_52_3_a13/ %G ru %F MZM_1992_52_3_a13