@article{MT_1987_7_a1,
     author = {O. L. Bezrukova and N. S. Dairbekov and A. P. Kopylov},
     title = {On mappings close in the $C$-norm to classes of solutions of linear elliptic systems of partial differential equations},
     journal = {Matemati\v{c}eskie trudy},
     pages = {19--30},
     publisher = {mathdoc},
     volume = {7},
     year = {1987},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MT_1987_7_a1/}
}