%0 Journal Article %A A. P. Buslaev %T Sharp constants and extremal functions in inequalities for derivatives %J Matematičeskie zametki %D 1987 %P 159-174 %V 41 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/MZM_1987_41_2_a4/ %G ru %F MZM_1987_41_2_a4