Bluman, G.W & Kumei, S <br/><br/>
Symmetries & differential equations 
G.W. Bluman & S. Kumei 
 - New York  Springer  1989 
 - xiii  412 
 - Applied mathematical sciences 81 .
<br/><br/><label>ISBN: </label>0387969969 
<br/><br/><label>Dewey Class. No.: </label>10.01+10.02+10.11  / BLUM