%0 Journal Article %A A. Kucia %A A. SzymaƄski %T There are absolute ultrafilters on N which are not minimal %J Colloquium Mathematicum %D 1971 %P 29-34 %V 37 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/cm-37-1-29-34/ %R 10.4064/cm-37-1-29-34 %G en %F 10_4064_cm_37_1_29_34