@article{ZNSL_1997_247_a4,
     author = {V. V. Kapustin},
     title = {Characteristic functions and their factorizations},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {71--78},
     publisher = {mathdoc},
     volume = {247},
     year = {1997},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1997_247_a4/}
}