@article{VSGU_2011_5_a5,
     author = {M. B. Medegei},
     title = {On one approximation estimate},
     journal = {Vestnik Samarskogo universiteta. Estestvennonau\v{c}na\^a seri\^a},
     pages = {53--59},
     publisher = {mathdoc},
     number = {5},
     year = {2011},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VSGU_2011_5_a5/}
}