@article{DAN_1980_254_5_a7,
     author = {A. A. Karelin},
     title = {On a boundary value problem with shift for a system of differential equations of elliptic-hyperbolic type},
     journal = {Doklady Akademii Nauk},
     pages = {1055--1060},
     publisher = {mathdoc},
     volume = {254},
     number = {5},
     year = {1980},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1980_254_5_a7/}
}