TY  - JOUR
AU  - Jens Heber
TI  - On the geometric rank of homogeneous spaces of nonpositive curvature.
JO  - Inventiones mathematicae
PY  - 1993
SP  - 151
EP  - 170
VL  - 112
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/IM_1993__112_3_144098/
ID  - IM_1993__112_3_144098
ER  -