Hydon, P.E <br/><br/>
Symmetry methods for differential equations  beginner's guide 
P.E. Hydon 
 - Cambridge  Cambridge University Press  2000 
 - xi  213 
 - Cambridge texts in applied mathematics .
<br/><br/><label>ISBN: </label>9780521497862 
<br/><br/><label>Dewey Class. No.: </label>10.01+10.13  / HYDO