@article{IVM_1995_2_a9,
     author = {V. G. Doronin and A. A. Ligun},
     title = {On a refinement of {Jackson-type} inequalities in the approximation of differentiable periodic functions by linear operators},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {79--82},
     publisher = {mathdoc},
     number = {2},
     year = {1995},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1995_2_a9/}
}