%0 Journal Article %A I. I. Parovichenko %T On some questions connected with the iteration of set-theoretic operations %J Sbornik. Mathematics %D 1978 %P 813-840 %V 34 %N 6 %U http://geodesic.mathdoc.fr/item/SM_1978_34_6_a6/ %G en %F SM_1978_34_6_a6