@article{IM2_1971_5_1_a6,
     author = {G. K. Lebed' and A. A. Avdeenko},
     title = {Approximation of periodic functions by {Fej\'er} suns},
     journal = {Izvestiya. Mathematics },
     pages = {86--96},
     publisher = {mathdoc},
     volume = {5},
     number = {1},
     year = {1971},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_1971_5_1_a6/}
}