@article{TM_1987_180_a79,
     author = {B. D. Kotlyar},
     title = {Fourier coefficients and densities of subsets of the series of natural numbers},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {140--141},
     year = {1987},
     volume = {180},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TM_1987_180_a79/}
}