%0 Journal Article
%A Yu. Sh. Abramov
%T Numerical ranges, zones, and spectra of families of selfadjoint operators
%J Doklady Akademii Nauk
%D 1981
%P 1033-1037
%V 257
%N 5
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1981_257_5_a0/
%G ru
%F DAN_1981_257_5_a0