@article{AIHPA_1989__51_2_199_0,
     author = {Lochak, P. and Porzio, A.},
     title = {A realistic exponential estimate for a paradigm hamiltonian},
     journal = {Annales de l'I.H.P. Physique th\'eorique},
     pages = {199--219},
     publisher = {Gauthier-Villars},
     volume = {51},
     number = {2},
     year = {1989},
     mrnumber = {1033617},
     zbl = {0699.70021},
     language = {en},
     url = {http://archive.numdam.org/item/AIHPA_1989__51_2_199_0/}
}