%0 Journal Article %A M. A. Shubin %T Factorization of parameter-dependent matrix-functions in normed rings and certain related questions in the theory of noetherian operators %J Sbornik. Mathematics %D 1967 %P 543-560 %V 2 %N 4 %I mathdoc %U http://geodesic.mathdoc.fr/item/SM_1967_2_4_a8/ %G en %F SM_1967_2_4_a8