%0 Journal Article %A N. K. Bari %A S. B. Stechkin %T Best approximations and differential properties of two conjugate functions %J Trudy Moskovskogo matematičeskogo obŝestva %D 1956 %P 483-522 %V 5 %I mathdoc %U http://geodesic.mathdoc.fr/item/MMO_1956_5_a11/ %G ru %F MMO_1956_5_a11