@article{DAN_1960_132_3_a9,
     author = {A. S. Markus},
     title = {basis from root vectors of a dissipative operator},
     journal = {Doklady Akademii Nauk},
     pages = {524--527},
     publisher = {mathdoc},
     volume = {132},
     number = {3},
     year = {1960},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1960_132_3_a9/}
}