@article{MZM_2006_80_5_a15,
     author = {Yu. V. Malykhin},
     title = {Estimates of trigonometric sums modulo $p^r$},
     journal = {Matemati\v{c}eskie zametki},
     pages = {793--796},
     publisher = {mathdoc},
     volume = {80},
     number = {5},
     year = {2006},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_2006_80_5_a15/}
}