@article{DAN_1977_237_1_a7,
     author = {V. I. Rozhkov and M. F. Korolev},
     title = {Periodic solutions of linear difference systems with a small difference},
     journal = {Doklady Akademii Nauk},
     pages = {35--38},
     publisher = {mathdoc},
     volume = {237},
     number = {1},
     year = {1977},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1977_237_1_a7/}
}