@article{IM2_1974_8_3_a11,
     author = {I. V. Gel'man and V. G. Maz'ya},
     title = {Estimates on the boundary for differential operators with constant coefficients in a~half-space},
     journal = {Izvestiya. Mathematics},
     pages = {667--726},
     year = {1974},
     volume = {8},
     number = {3},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_1974_8_3_a11/}
}