@article{MAN_1992__293_4_164970,
     author = {William J. Floyd},
     title = {Growth of planar {Coxeter} groups, {P.V.} numbers, and {Salem} numbers.},
     journal = {Mathematische Annalen},
     pages = {475--484},
     publisher = {mathdoc},
     volume = {293},
     number = {4},
     year = {1992},
     zbl = {0735.51016},
     url = {http://geodesic.mathdoc.fr/item/MAN_1992__293_4_164970/}
}