@article{ASENS_1995_4_28_5_549_0,
     author = {Gaboriau, Damien and Levitt, Gilbert},
     title = {The rank of actions on $R$-trees},
     journal = {Annales scientifiques de l'\'Ecole Normale Sup\'erieure},
     pages = {549--570},
     publisher = {Elsevier},
     volume = {Ser. 4, 28},
     number = {5},
     year = {1995},
     doi = {10.24033/asens.1725},
     zbl = {0835.20038},
     mrnumber = {1341661},
     language = {en},
     url = {http://www.numdam.org/articles/10.24033/asens.1725/}
}