@article{SEDP_1987-1988____A14_0,
     author = {Herman, Michael R.},
     title = {Existence et non existence de tores invariants par des diff\'eomorphismes symplectiques},
     journal = {S\'eminaire \'Equations aux d\'eriv\'ees partielles (Polytechnique) dit aussi "S\'eminaire Goulaouic-Schwartz"},
     note = {talk:14},
     pages = {1--24},
     publisher = {Ecole Polytechnique, Centre de Math\'ematiques},
     year = {1987-1988},
     mrnumber = {1018186},
     zbl = {0664.58005},
     language = {fr},
     url = {http://archive.numdam.org/item/SEDP_1987-1988____A14_0/}
}