@article{MZM_1982_32_5_a13, author = {N. M. Miroshin and V. V. Khromov}, title = {A problem of best approximation of functions of several variables}, journal = {Matemati\v{c}eskie zametki}, pages = {721--727}, publisher = {mathdoc}, volume = {32}, number = {5}, year = {1982}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1982_32_5_a13/} }