@article{DAN_1958_118_2_a10,
     author = {Sun Yong-sheng},
     title = {On the best approximation of classes of functions representable in the convolution form},
     journal = {Doklady Akademii Nauk},
     pages = {247--250},
     publisher = {mathdoc},
     volume = {118},
     number = {2},
     year = {1958},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1958_118_2_a10/}
}