@article{RLIN_1990_9_1_1_a4,
     author = {Girardi, Mario and Matzeu, Michele},
     title = {Convergence results for periodic solutions of nonautonomous {Hamiltonian} systems},
     journal = {Atti della Accademia nazionale dei Lincei. Rendiconti Lincei. Matematica e applicazioni},
     pages = {21--28},
     publisher = {mathdoc},
     volume = {Ser. 9, 1},
     number = {1},
     year = {1990},
     zbl = {0698.70014},
     mrnumber = {615860},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/RLIN_1990_9_1_1_a4/}
}