Ballmann, Werner. <br/><br/>
Manifolds of nonpositive curvature/ 
Werner Ballmann, Mikhael Gromov, Viktor Schroeder. 
 - Boston:  Birkhäuser,  1985. 
 - iv, 263 p.:  ill.;  23 cm. 
 - Progress in mathematics ;  vol. 61. .
 - Progress in mathematics; .
<br/><br/> Based on four lectures delivered by M. Gromov in Feb. 1981 at Collège de France, Paris, with appendices by W. Ballmann and V. Schroeder.  Includes index. 
<br/><br/>Bibliography: p. 256-259. 
<br/><br/><label>ISBN: </label>081763181X 
<br/><br/><label>LCCN: </label>85020149 //r892 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Geometry, Differential.<br/>Manifolds (Mathematics)
<br/><br/><label>Dewey Class. No.: </label>516.36  / B192m