@article{SM_1999_190_7_a2,
     author = {I. M. Petrushko},
     title = {Existence of boundary values for solutions of degenerate elliptic equations},
     journal = {Sbornik. Mathematics},
     pages = {973--1004},
     publisher = {mathdoc},
     volume = {190},
     number = {7},
     year = {1999},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_1999_190_7_a2/}
}