@article{BSMF_2011__139_4_479_0,
     author = {Barr\'e, Sylvain and Pichot, Mika\"el},
     title = {The 4-string braid group $B_4$ has property {RD} and exponential mesoscopic rank},
     journal = {Bulletin de la Soci\'et\'e Math\'ematique de France},
     pages = {479--502},
     publisher = {Soci\'et\'e math\'ematique de France},
     volume = {139},
     number = {4},
     year = {2011},
     doi = {10.24033/bsmf.2615},
     mrnumber = {2869301},
     zbl = {1266.20046},
     language = {en},
     url = {http://archive.numdam.org/articles/10.24033/bsmf.2615/}
}