@article{DAN_1966_167_4_a5,
     author = {I. A. Novosel'skii},
     title = {Some criteria for the completeness of the system of root-vectors of a linear operator in space with two norms},
     journal = {Doklady Akademii Nauk},
     pages = {747--750},
     publisher = {mathdoc},
     volume = {167},
     number = {4},
     year = {1966},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1966_167_4_a5/}
}