%0 Journal Article %A A. G. El'kin %T Irreducible spaces, and ultrafilters topologically dense in themselves %J Doklady Akademii Nauk %D 1969 %P 464-467 %V 189 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/DAN_1969_189_3_a3/ %G ru %F DAN_1969_189_3_a3