@article{GDZPPN002098709,
title = {On the Entropy of the Geodesic Flow in Manifolds Without Conjugate Points.},
journal = {Inventiones mathematicae},
volume = {69},
year = {1982},
pages = {375-392},
zbl = {0476.58019},
url = {http://dml.mathdoc.fr/item/GDZPPN002098709}
}
Freire, A.; Mane, R. On the Entropy of the Geodesic Flow in Manifolds Without Conjugate Points.. Inventiones mathematicae, Tome 69 (1982) pp. 375-392. http://gdmltest.u-ga.fr/item/GDZPPN002098709/