@article{DE_2003_39_10_a16,
     author = {Yu. V. Usachev},
     title = {Bifurcation of an {Invariant} {Torus} from an {Equilibrium} {Under} {Commensurability} {Conditions}},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1434--1436},
     publisher = {mathdoc},
     volume = {39},
     number = {10},
     year = {2003},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_2003_39_10_a16/}
}