%0 Journal Article %A W. Słowikowski %T Range of operators and regularity of solutions %J Studia Mathematica %D 1971 %P 183-198 %V 40 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/sm-40-2-183-198/ %R 10.4064/sm-40-2-183-198 %G en %F 10_4064_sm_40_2_183_198