@article{DAN_1967_173_5_a1,
     author = {E. G. Gol'shtein},
     title = {Problems of best approximation by elements of a convex set and some properties of the support functionals},
     journal = {Doklady Akademii Nauk},
     pages = {995--998},
     publisher = {mathdoc},
     volume = {173},
     number = {5},
     year = {1967},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1967_173_5_a1/}
}