@article{MZM_1980_28_5_a6,
     author = {L. P. Vlasov},
     title = {A characterization of generalized and classical best approximation elements relative to spaces of finite codimension},
     journal = {Matemati\v{c}eskie zametki},
     pages = {707--716},
     publisher = {mathdoc},
     volume = {28},
     number = {5},
     year = {1980},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1980_28_5_a6/}
}