@article{DAN_1981_258_2_a8,
     author = {P. A. Kuchment},
     title = {On {Floquet} theory for parabolic and elliptic boundary value problems in a cylinder},
     journal = {Doklady Akademii Nauk},
     pages = {296--299},
     publisher = {mathdoc},
     volume = {258},
     number = {2},
     year = {1981},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1981_258_2_a8/}
}