%0 Journal Article
%A Andreas Blass
%T Two closed categories of filters
%J Fundamenta Mathematicae
%D 1977
%P 129-143
%V 94
%N 2
%I mathdoc
%U http://geodesic.mathdoc.fr/articles/10.4064/fm-94-2-129-143/
%R 10.4064/fm-94-2-129-143
%G en
%F 10_4064_fm_94_2_129_143