@article{AIHPC_1987__4_4_307_0,
     author = {Ekeland, I. and Lassoued, L.},
     title = {Multiplicit\'e des trajectoires ferm\'ees de syst\`emes hamiltoniens connexes},
     journal = {Annales de l'I.H.P. Analyse non lin\'eaire},
     pages = {307--335},
     publisher = {Gauthier-Villars},
     volume = {4},
     number = {4},
     year = {1987},
     mrnumber = {917740},
     zbl = {0633.58034},
     language = {fr},
     url = {http://www.numdam.org/item/AIHPC_1987__4_4_307_0/}
}