@article{MZ_1978__159_172659,
     author = {Gudlaugur Thorbergsson},
     title = {Clodes {Geodesics} on {Non-Compact} {Riemannian} {Manifolds.}},
     journal = {Mathematische Zeitschrift},
     pages = {249--258},
     publisher = {mathdoc},
     volume = {159},
     year = {1978},
     zbl = {0358.53027},
     url = {http://geodesic.mathdoc.fr/item/MZ_1978__159_172659/}
}