@article{SM_1970_11_1_a7,
     author = {B. L. Fridman},
     title = {An estimate of the dimension of the null spaces of linear superpositions},
     journal = {Sbornik. Mathematics},
     pages = {101--114},
     publisher = {mathdoc},
     volume = {11},
     number = {1},
     year = {1970},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_1970_11_1_a7/}
}