@article{MZM_1982_32_5_a8,
     author = {N. P. Korneichuk},
     title = {Precise constant in {Jackson's} inequality for continuous periodic functions},
     journal = {Matemati\v{c}eskie zametki},
     pages = {669--674},
     publisher = {mathdoc},
     volume = {32},
     number = {5},
     year = {1982},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1982_32_5_a8/}
}