@article{MZM_2011_89_5_a12,
     author = {M. R. Haddadi and H. Mazaheri},
     title = {Best {Approximation} in {Vector} {Spaces}},
     journal = {Matemati\v{c}eskie zametki},
     pages = {788--793},
     publisher = {mathdoc},
     volume = {89},
     number = {5},
     year = {2011},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_2011_89_5_a12/}
}