@article{MAN_1984__268_182927,
     author = {Helmut Hofer and John Toland},
     title = {Homoclinic, {Heteroclinic,} and {Periodic} {Orbits} for a {Class} of {Indefinite} {Hamiltonian} {Systems.}},
     journal = {Mathematische Annalen},
     pages = {387--404},
     publisher = {mathdoc},
     volume = {268},
     year = {1984},
     zbl = {0569.70017},
     url = {http://geodesic.mathdoc.fr/item/MAN_1984__268_182927/}
}