@article{MMO_1956_5_a11,
     author = {N. K. Bari and S. B. Stechkin},
     title = {Best approximations and differential properties of two conjugate functions},
     journal = {Trudy Moskovskogo matemati\v{c}eskogo ob\^{s}estva},
     pages = {483--522},
     publisher = {mathdoc},
     volume = {5},
     year = {1956},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MMO_1956_5_a11/}
}