@article{IVM_1960_2_a6,
     author = {I. Gohberg and A. S. Markus},
     title = {Characteristic properties of certain points of the spectrum of bounded linear operators},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {74--87},
     year = {1960},
     number = {2},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1960_2_a6/}
}