@article{ZNSL_1996_232_a2,
     author = {O. L. Vinogradov},
     title = {Sharp inequalities for the second modulus of continuity of periodic functions and of functions extended from the segment},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {33--49},
     publisher = {mathdoc},
     volume = {232},
     year = {1996},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1996_232_a2/}
}