TY  - GEN
AU  - Ballmann, Werner
TI  - Lectures on spaces of nonpositive curvature: With an appendix by Misha Brin ergodicity of geodesic flows
SN  - 3764352426
PY  - 1995///
CY  - Basel, Boston
PB  - Birkhauser
KW  - Rank rigidity
N1  - Contine bibliogr. si index
ER  -