@article{DAN_1961_137_3_a10,
     author = {V. N. Trofimov},
     title = {Linear methods of approximation to continuous periodic functions of two variables},
     journal = {Doklady Akademii Nauk},
     pages = {531--532},
     publisher = {mathdoc},
     volume = {137},
     number = {3},
     year = {1961},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1961_137_3_a10/}
}