@article{MZM_1983_34_3_a10,
     author = {A. I. Ibragimov},
     title = {Some qualitative theorems for degenerate elliptic equations},
     journal = {Matemati\v{c}eskie zametki},
     pages = {407--416},
     publisher = {mathdoc},
     volume = {34},
     number = {3},
     year = {1983},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1983_34_3_a10/}
}