%0 Journal Article %A Szal, Bogdan %T Trigonometric approximation by Nörlund type means in $L^p$-norm %J Commentationes Mathematicae Universitatis Carolinae %D 2009 %P 575-589 %V 50 %N 4 %I mathdoc %U http://geodesic.mathdoc.fr/item/CMUC_2009__50_4_a7/ %G en %F CMUC_2009__50_4_a7