@article{DAN_1978_242_1_a4,
     author = {M. A. Gol'dman and S. N. Krachkovskii},
     title = {Some remarks on perturbations of closed linear operators with closed range},
     journal = {Doklady Akademii Nauk},
     pages = {25--27},
     publisher = {mathdoc},
     volume = {242},
     number = {1},
     year = {1978},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1978_242_1_a4/}
}