@article{ZNSL_1976_58_a2,
     author = {Yu. K. Dem'yanovich},
     title = {Estimates of rate of convergence of best approximations by local functions},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {22--37},
     year = {1976},
     volume = {58},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1976_58_a2/}
}