@article{MZM_2014_95_2_a5,
     author = {A. G. Medvedev},
     title = {Conservation of {Hyperbolic} {Tori} in {Hamiltonian} {Systems}},
     journal = {Matemati\v{c}eskie zametki},
     pages = {227--233},
     publisher = {mathdoc},
     volume = {95},
     number = {2},
     year = {2014},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_2014_95_2_a5/}
}