@article{IM2_1977_11_5_a7,
     author = {A. A. Zhensykbaev},
     title = {Best quadrature formula for some classes of periodic differentiable functions},
     journal = {Izvestiya. Mathematics},
     pages = {1055--1071},
     year = {1977},
     volume = {11},
     number = {5},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_1977_11_5_a7/}
}