%0 Journal Article
%A O. I. Zavialov
%T ``Non-physical'' thresholds in the perturbation theory
%J Doklady Akademii Nauk
%D 1960
%P 64-67
%V 133
%N 1
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1960_133_1_a15/
%G ru
%F DAN_1960_133_1_a15