%0 Journal Article %A S. L. Krushkal' %T Extremal quasiconformal mappings with a given boundary correspondence %J Doklady Akademii Nauk %D 1967 %P 525-527 %V 175 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/DAN_1967_175_3_a4/ %G ru %F DAN_1967_175_3_a4