@article{DAN_1970_193_5_a0,
     author = {M.-B. A. Babaev},
     title = {The approximation of polynomials of two variables by functions of the form $\varphi(x)+\psi(y)$},
     journal = {Doklady Akademii Nauk},
     pages = {967--969},
     publisher = {mathdoc},
     volume = {193},
     number = {5},
     year = {1970},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1970_193_5_a0/}
}