@article{RM_1967_22_2_a17,
     author = {A. V. Efimov},
     title = {Summation of orthogonal series by linear methods},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     year = {1967},
     volume = {22},
     number = {2},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/RM_1967_22_2_a17/}
}