%0 Journal Article %A V. I. Matsaev %A E. Z. Mogulski %T On the possibility of weak perturbation of a complete operator up to a Volterra operator %J Doklady Akademii Nauk %D 1972 %P 534-537 %V 207 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/DAN_1972_207_3_a6/ %G ru %F DAN_1972_207_3_a6