@article{DAN_1963_152_6_a10,
     author = {F. S. Rofe-Beketov},
     title = {On the spectrum of non-selfadjoint differential operators with periodic coefficients},
     journal = {Doklady Akademii Nauk},
     pages = {1312--1315},
     publisher = {mathdoc},
     volume = {152},
     number = {6},
     year = {1963},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1963_152_6_a10/}
}