@article{SM_1985_50_1_a10,
     author = {A. I. Ibragimov},
     title = {Some qualitative properties of solutions of the mixed problem for equations of elliptic type},
     journal = {Sbornik. Mathematics},
     pages = {163--176},
     year = {1985},
     volume = {50},
     number = {1},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_1985_50_1_a10/}
}