@article{GDZPPN002442159,
title = {Fixed sets and free subgroups of groups acting on metric spaces.},
journal = {Mathematische Zeitschrift},
volume = {212},
year = {1993},
pages = {425-440},
zbl = {0892.54022},
url = {http://dml.mathdoc.fr/item/GDZPPN002442159}
}
Woess, Wolfgang. Fixed sets and free subgroups of groups acting on metric spaces.. Mathematische Zeitschrift, Tome 212 (1993) pp. 425-440. http://gdmltest.u-ga.fr/item/GDZPPN002442159/