@article{02206527, title = {Limit groups and groups acting freely on }, journal = {Geometry \& Topology}, volume = {8}, year = {2004}, pages = {1427-1470}, doi = {10.2140/gt.2004.8.1427}, zbl = {1114.20013}, language = {en}, url = {http://dml.mathdoc.fr/item/02206527} }
Guirardel, Vincent. Limit groups and groups acting freely on . Geometry & Topology, Tome 8 (2004) pp. 1427-1470. doi : 10.2140/gt.2004.8.1427. http://gdmltest.u-ga.fr/item/02206527/