@article{MZM_1976_20_4_a5,
     author = {Yu. L. Shmul'yan},
     title = {Some stability properties for analytic operator functions},
     journal = {Matemati\v{c}eskie zametki},
     pages = {511--520},
     publisher = {mathdoc},
     volume = {20},
     number = {4},
     year = {1976},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1976_20_4_a5/}
}