@article{IM2_2000_64_2_a1,
     author = {A. A. Karatsuba},
     title = {Weighted character sums},
     journal = {Izvestiya. Mathematics },
     pages = {249--263},
     publisher = {mathdoc},
     volume = {64},
     number = {2},
     year = {2000},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_2000_64_2_a1/}
}