@article{DAN_1960_134_6_a11,
     author = {V. Ya. Urm},
     title = {Reduction of systems of difference equations to canonical form},
     journal = {Doklady Akademii Nauk},
     pages = {1309--1312},
     publisher = {mathdoc},
     volume = {134},
     number = {6},
     year = {1960},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1960_134_6_a11/}
}