@article{TRSPY_1987_180_a8,
     author = {M.-B. Babayev},
     title = {The approximation of sobolev classes of functions by sums of products of functions of fewer variables},
     journal = {Informatics and Automation},
     pages = {30--32},
     publisher = {mathdoc},
     volume = {180},
     year = {1987},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TRSPY_1987_180_a8/}
}