@article{ZNSL_1998_255_a4,
     author = {V. V. Kapustin},
     title = {Operators close to unitary and their function models.~1},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {82--91},
     publisher = {mathdoc},
     volume = {255},
     year = {1998},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1998_255_a4/}
}