@article{ZNSL_1994_217_a5,
     author = {V. V. Kapustin},
     title = {Function calculus for almost isometric operators},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {59--73},
     publisher = {mathdoc},
     volume = {217},
     year = {1994},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1994_217_a5/}
}