@article{FAA_1991_25_4_a0,
     author = {S. N. Naboko},
     title = {Structure of the singularities of operator functions with a positive imaginary part},
     journal = {Funkcionalʹnyj analiz i ego prilo\v{z}eni\^a},
     pages = {1--13},
     publisher = {mathdoc},
     volume = {25},
     number = {4},
     year = {1991},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FAA_1991_25_4_a0/}
}