@article{TRSPY_1983_164_a10,
     author = {K. Tandori},
     title = {Orthogonal series and approximations of functions},
     journal = {Informatics and Automation},
     pages = {169--179},
     publisher = {mathdoc},
     volume = {164},
     year = {1983},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TRSPY_1983_164_a10/}
}