%0 Journal Article %A V. P. Motornyi %T Some extremal problems of theory of quadrature and approximation of functions %J Matematičeskie zametki %D 1976 %P 299-311 %V 19 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/MZM_1976_19_2_a14/ %G ru %F MZM_1976_19_2_a14