Olver, P.J <br/><br/>
Equivalence, invariants, & symmetry 
P.J. Olver 
 - Cambridge  Cambridge University Press  2008 
 - xvi  525 
<br/><br/><label>ISBN: </label>9780521101042 
<br/><br/><label>Dewey Class. No.: </label>515.3  / OLV