TY - JOUR AU - V. V. Ivanov TI - Uniformly summable semigroups of operators. II.~Perturbation of semigroups JO - Matematičeskie trudy PY - 1987 SP - 159 EP - 182 VL - 9 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/MT_1987_9_a14/ LA - ru ID - MT_1987_9_a14 ER -