%0 Journal Article
%A V. I. Ponomarev
%A V. V. Tkachuk
%T The countable character of $X$ in $\beta X$ versus the countable character of the diagonal in $X\times X$
%J Vestnik Moskovskogo universiteta. Matematika, mehanika
%D 1987
%P 16-19
%N 5
%I mathdoc
%U http://geodesic.mathdoc.fr/item/VMUMM_1987_5_a3/
%G ru
%F VMUMM_1987_5_a3