@article{DAN_1966_170_3_a5,
     author = {S. M. Nikol'skii},
     title = {Constructive representation of the zero-classes of differentiable functions of several variables},
     journal = {Doklady Akademii Nauk},
     pages = {512--515},
     publisher = {mathdoc},
     volume = {170},
     number = {3},
     year = {1966},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1966_170_3_a5/}
}