@article{DE_1989_25_6_a29,
     author = {V. P. Ruzaev},
     title = {On the bifurcation of an invariant torus $\mathbf T^m\to\mathbf T^{m+1}$},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1066--1069},
     publisher = {mathdoc},
     volume = {25},
     number = {6},
     year = {1989},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1989_25_6_a29/}
}