Gunther, P <br/><br/>
Huygens' principle & hyperbolic equations 
P. Gunther 
 - Boston  Academic Press  1988 
 - lvii  847 
 - Perspectives in mathematics 5 .
<br/><br/><label>ISBN: </label>0123073308 
<br/><br/><label>Dewey Class. No.: </label>10.05  / GUNT