TY  - BOOK
AU  - Ballmann, Werner
AU  - 
TI  - Lectures on spaces of nonpositive curvature
T2  - DMV Seminar band 
SN  - 0817652426
U1  - 516 
PY  - 1995///
CY  - Basel
PB  - Birkhauser Verlag
N1  - With an appendix by Misha Brin Ergodicity of Geodesic Flows
ER  -