@article{DAN_1957_112_2_a4,
     author = {B. M. Naimark},
     title = {The completeness of the system of eigenfunctions and adjoined functions of strongly elliptic systems of differential equations},
     journal = {Doklady Akademii Nauk},
     pages = {198--201},
     publisher = {mathdoc},
     volume = {112},
     number = {2},
     year = {1957},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1957_112_2_a4/}
}