@article{MM2_1986__57_155203,
     author = {Vittorio Coti Zelati},
     title = {Remarks on dynamical systems with weak forces.},
     journal = {Manuscripta mathematica},
     pages = {417--424},
     publisher = {mathdoc},
     volume = {57},
     year = {1986},
     zbl = {0606.58039},
     url = {http://geodesic.mathdoc.fr/item/MM2_1986__57_155203/}
}