@article{TM_1987_180_a4,
     author = {Sh. A. Alimov},
     title = {On the membership of the gradient of a~harmonic function in {S.} {M.~Nikol'skij's} class},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {25--27},
     year = {1987},
     volume = {180},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TM_1987_180_a4/}
}