@article{SM_2018_209_6_a5,
     author = {P. V. Paramonov},
     title = {Criteria for the individual $C^m$-approximability of~functions on compact subsets of~$\mathbb R^N$ by solutions of second-order homogeneous elliptic equations},
     journal = {Sbornik. Mathematics},
     pages = {857--870},
     publisher = {mathdoc},
     volume = {209},
     number = {6},
     year = {2018},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_2018_209_6_a5/}
}