%0 Journal Article
%A Z. K. Litvintseva
%T The complexity of certain problems for groups and semigroups
%J Doklady Akademii Nauk
%D 1970
%P 989-992
%V 191
%N 5
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1970_191_5_a7/
%G ru
%F DAN_1970_191_5_a7