@article{DAN_1976_226_1_a11,
     author = {M. I. Levin and Yu. M. Girshovich and V. K. Arro},
     title = {Best quadrature formulas on sets of functions},
     journal = {Doklady Akademii Nauk},
     pages = {51--54},
     publisher = {mathdoc},
     volume = {226},
     number = {1},
     year = {1976},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1976_226_1_a11/}
}