%0 Journal Article %A A. A. Dezin %T On problems for linear differential operations %J Sbornik. Mathematics %D 1987 %P 411-419 %V 57 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/SM_1987_57_2_a5/ %G en %F SM_1987_57_2_a5