@article{SM_1973_21_1_a4,
     author = {A. I. Komech},
     title = {Elliptic boundary value problems on manifolds with a~piecewise smooth boundary},
     journal = {Sbornik. Mathematics},
     pages = {91--135},
     publisher = {mathdoc},
     volume = {21},
     number = {1},
     year = {1973},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_1973_21_1_a4/}
}