@article{FAA_1967_1_1_a3,
     author = {I. Ts. Gokhberg and M. G. Krein},
     title = {Description of contraction operators which are similar to unitary operators},
     journal = {Funkcionalʹnyj analiz i ego prilo\v{z}eni\^a},
     pages = {38--60},
     publisher = {mathdoc},
     volume = {1},
     number = {1},
     year = {1967},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FAA_1967_1_1_a3/}
}