@article{DAN_1964_157_4_a4,
     author = {\`E. M. Dzhabrailova},
     title = {The completeness of finite-dimensional invariant sub-spaces of a non-selfadjoint singular differential operator 
},
     journal = {Doklady Akademii Nauk},
     pages = {774--776},
     publisher = {mathdoc},
     volume = {157},
     number = {4},
     year = {1964},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1964_157_4_a4/}
}