@article{RM_1978_33_4_a1,
     author = {V. M. Badkov},
     title = {Approximation properties of {Fourier} series in orthogonal polynomials},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {53--117},
     publisher = {mathdoc},
     volume = {33},
     number = {4},
     year = {1978},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/RM_1978_33_4_a1/}
}