@article{DAN_1964_154_3_a8,
     author = {V. I. Nechaev},
     title = {A best-possible estimate of trigonometric sums for recurrent functions with non-constant coefficients},
     journal = {Doklady Akademii Nauk},
     pages = {520--522},
     publisher = {mathdoc},
     volume = {154},
     number = {3},
     year = {1964},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1964_154_3_a8/}
}