%0 Journal Article %A Krystyna Skórnik %T Sobolev's and local derivatives %J Studia Mathematica %D 1983 %P 509-517 %V 77 %N 5 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/sm-77-5-509-517/ %R 10.4064/sm-77-5-509-517 %G en %F 10_4064_sm_77_5_509_517