@article{MZM_2021_109_5_a8,
     author = {A. Yu. Popov},
     title = {Refinement of {Estimates} of {Sums} of {Sine} {Series} with {Monotone} {Coefficients} and {Cosine} {Series} with {Convex} {Coefficients}},
     journal = {Matemati\v{c}eskie zametki},
     pages = {768--780},
     publisher = {mathdoc},
     volume = {109},
     number = {5},
     year = {2021},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_2021_109_5_a8/}
}