@article{DAN_1957_115_5_a6,
     author = {M. K. Fage},
     title = {Integral representations of analytical operator functions of one variable},
     journal = {Doklady Akademii Nauk},
     pages = {874--877},
     publisher = {mathdoc},
     volume = {115},
     number = {5},
     year = {1957},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1957_115_5_a6/}
}