@article{ZNSL_1991_191_a10,
     author = {V. I. Kopejko},
     title = {On an {Ojanguren's} theorem},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {124--125},
     publisher = {mathdoc},
     volume = {191},
     year = {1991},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1991_191_a10/}
}