TY  - JOUR
AU  - J. Mennicke
AU  - J. Elstrodt
AU  - F. Grunewald
TI  - Kloosterman sums for Clifford algebras and a lower bound for the positive eigenvalues of the Laplacian for congruence subgroups acting on hyperbolic spaces.
JO  - Inventiones mathematicae
PY  - 1990
SP  - 641
EP  - 686
VL  - 101
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/IM_1990__101_2_143820/
ID  - IM_1990__101_2_143820
ER  -