@article{TRSPY_1989_190_a0,
     author = {A. S. Belov},
     title = {On the coefficients of trigonometric cosine-series with non-negative partial sums},
     journal = {Informatics and Automation},
     pages = {3--21},
     publisher = {mathdoc},
     volume = {190},
     year = {1989},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TRSPY_1989_190_a0/}
}