@article{MZM_1999_66_2_a11,
     author = {M. K. Potapov},
     title = {Coincidence of classes of functions defined by the generalized shift operator or by the order of best polynomial approximation},
     journal = {Matemati\v{c}eskie zametki},
     pages = {242--257},
     publisher = {mathdoc},
     volume = {66},
     number = {2},
     year = {1999},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1999_66_2_a11/}
}