@article{VMJ_2004_6_4_a6,
     author = {G. G. Magaril-Il'yaev},
     title = {Optimal interpolation and the {Lagrange} principle},
     journal = {Vladikavkazskij matemati\v{c}eskij \v{z}urnal},
     pages = {42--47},
     publisher = {mathdoc},
     volume = {6},
     number = {4},
     year = {2004},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMJ_2004_6_4_a6/}
}