@article{MZM_1974_16_2_a18,
     author = {V. I. Berdyshev},
     title = {Estimate of the modulus of continuity of the operator grad {F}},
     journal = {Matemati\v{c}eskie zametki},
     pages = {349--360},
     publisher = {mathdoc},
     volume = {16},
     number = {2},
     year = {1974},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1974_16_2_a18/}
}