%0 Journal Article
%A E. G. Pytkeev
%A A. G. Chentsov
%T Open ultrafilters and separability with the use of the operation of closure
%J Trudy Instituta matematiki i mehaniki
%D 2016
%P 212-225
%V 22
%N 3
%I mathdoc
%U http://geodesic.mathdoc.fr/item/TIMM_2016_22_3_a21/
%G ru
%F TIMM_2016_22_3_a21