@article{DAN_1979_245_4_a5,
     author = {S. A. Pichugov},
     title = {On the multidimensional {Jackson} theorem for linear polynomial approximations},
     journal = {Doklady Akademii Nauk},
     pages = {792--794},
     publisher = {mathdoc},
     volume = {245},
     number = {4},
     year = {1979},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1979_245_4_a5/}
}