@article{TSG_1989-1990__8__19_0, author = {Fran\c{c}oise Dal'bo}, title = {Des groupes magiques ou quand des sous-groupes libres affines op\`erent proprement discontin\^ument sur $\mathbf {R}^3$}, journal = {S\'eminaire de th\'eorie spectrale et g\'eom\'etrie}, pages = {19--26}, publisher = {Institut Fourier}, address = {Grenoble}, volume = {8}, year = {1989-1990}, doi = {10.5802/tsg.74}, zbl = {0821.20023}, mrnumber = {1717280}, language = {fr}, url = {https://proceedings.centre-mersenne.org/articles/10.5802/tsg.74/} }