@article{SM_1991_68_1_a9,
     author = {D. V. Treshch\"ev},
     title = {The mechanism of destruction of resonance tori of {Hamiltonian} systems},
     journal = {Sbornik. Mathematics},
     pages = {181--203},
     year = {1991},
     volume = {68},
     number = {1},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_1991_68_1_a9/}
}