TY - JOUR AU - E. Leuzinger TI - Tits Geometry, Arithmetic Groups, and the Proof of a Conjecture of Siegel JO - Journal of Lie Theory PY - 2004 SP - 317 EP - 338 VL - 14 IS - 2 UR - http://geodesic.mathdoc.fr/item/JOLT_2004_14_2_a0/ ID - JOLT_2004_14_2_a0 ER -