@article{10_2140_agt_2006_6_1987,
     author = {Caprace, Pierre-Emmanuel},
     title = {Conjugacy of 2{\textendash}spherical subgroups of {Coxeter} groups and parallel walls},
     journal = {Algebraic and Geometric Topology},
     pages = {1987--2029},
     year = {2006},
     volume = {6},
     number = {4},
     doi = {10.2140/agt.2006.6.1987},
     url = {http://geodesic.mathdoc.fr/articles/10.2140/agt.2006.6.1987/}
}