@article{GDZPPN002102854,
title = {Local convexity and nonnegative curvature - Gromov's proof of the sphere theorem.},
journal = {Inventiones mathematicae},
volume = {83},
year = {1986},
pages = {507-522},
zbl = {0594.53034},
url = {http://dml.mathdoc.fr/item/GDZPPN002102854}
}
Eschenburg, J.-H. Local convexity and nonnegative curvature - Gromov's proof of the sphere theorem.. Inventiones mathematicae, Tome 83 (1986) pp. 507-522. http://gdmltest.u-ga.fr/item/GDZPPN002102854/