%0 Journal Article %A L. N. Slobodetskiǐ %T S. L. Sobolev's spaces of fractional order and their application to boundary problems for partial differential equations %J Doklady Akademii Nauk %D 1958 %P 243-246 %V 118 %N 2 %U http://geodesic.mathdoc.fr/item/DAN_1958_118_2_a9/ %G ru %F DAN_1958_118_2_a9