%0 Journal Article
%T Letter to the editors
%J Journal of the Belarusian State University. Mathematics and Informatics
%D 2019
%P 33-34
%V 1
%I mathdoc
%U http://geodesic.mathdoc.fr/item/BGUMI_2019_1_a4/
%G ru
%F BGUMI_2019_1_a4