@article{FAA_1988_22_1_a7,
     author = {L. M. Gershtein},
     title = {Perturbation of the generating operator of an analytic semigroup},
     journal = {Funkcionalʹnyj analiz i ego prilo\v{z}eni\^a},
     pages = {62--63},
     publisher = {mathdoc},
     volume = {22},
     number = {1},
     year = {1988},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FAA_1988_22_1_a7/}
}