Discrete subgroups of semisimple Lie groups  
Margulis, G. A. 
 - Berlin ; | New York :  Springer-Verlag,  1991 
 - ix, 388 p. :  ill. ;  25 cm. 
<br/><br/> Includes index. 
<br/><br/><label>ISBN: </label>9783540121794 (hbk.: