@article{FPM_2018_22_1_a2,
     author = {A. S. Belov},
     title = {On unimprovability of some theorems on convergence in mean of trigonometric series},
     journal = {Fundamentalʹna\^a i prikladna\^a matematika},
     pages = {31--49},
     publisher = {mathdoc},
     volume = {22},
     number = {1},
     year = {2018},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FPM_2018_22_1_a2/}
}