%0 Journal Article %A Bernardo López Melero %T A negative result in differentiation theory %J Studia Mathematica %D 1982 %P 173-182 %V 72 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/sm-72-2-173-182/ %R 10.4064/sm-72-2-173-182 %G en %F 10_4064_sm_72_2_173_182