%0 Journal Article
%A N. M. Dobrovol'skaya
%A V. A. Ponomarev
%T A~pair of counter-operators
%J Trudy Matematicheskogo Instituta imeni V.A. Steklova
%D 1965
%V 20
%N 6
%I mathdoc
%U http://geodesic.mathdoc.fr/item/RM_1965_20_6_a12/
%G ru
%F RM_1965_20_6_a12