@article{MZM_1971_9_5_a13,
     author = {V. M. Tikhomirov},
     title = {Some problems in approximation theory},
     journal = {Matemati\v{c}eskie zametki},
     pages = {593--607},
     year = {1971},
     volume = {9},
     number = {5},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1971_9_5_a13/}
}