@article{MZ_1993__214_1_174581,
     author = {D.B. Shapiro and E. Fluckiger-Bayer},
     title = {Hyperbolic involutions.},
     journal = {Mathematische Zeitschrift},
     pages = {461--476},
     year = {1993},
     volume = {214},
     number = {1},
     zbl = {0796.16029},
     url = {http://geodesic.mathdoc.fr/item/MZ_1993__214_1_174581/}
}