@article{SM_1973_20_3_a7,
     author = {A. S. Demidov},
     title = {Elliptic pseudodifferential boundary value problems with a~small parameter in the coefficient of the leading operator},
     journal = {Sbornik. Mathematics},
     pages = {439--463},
     publisher = {mathdoc},
     volume = {20},
     number = {3},
     year = {1973},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_1973_20_3_a7/}
}