%0 Journal Article
%A P. P. Zabreiko
%A M. A. Krasnosel'skii
%A E. I. Pustyl'nik
%T A~problem on fractional powers of 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_a13/
%G ru
%F RM_1965_20_6_a13