@article{ASENS_1987_4_20_1_89_0,
     author = {Rohlfs, J\"urgen and Speh, Birgit},
     title = {Representations with cohomology in the discrete spectrum of subgroups of ${\rm SO}(n,1)({Z})$ and {Lefschetz} numbers},
     journal = {Annales scientifiques de l'\'Ecole Normale Sup\'erieure},
     pages = {89--136},
     publisher = {Elsevier},
     volume = {Ser. 4, 20},
     number = {1},
     year = {1987},
     doi = {10.24033/asens.1525},
     mrnumber = {88h:22019},
     zbl = {0626.22010},
     language = {en},
     url = {http://archive.numdam.org/articles/10.24033/asens.1525/}
}