Ghoussoub, N <br/><br/>
Duality & perturbation methods in critical point theory 
N. Ghoussoub 
 - Cambridge  Cambridge University Press  1993 
 - xviii  258 
 - Cambridge tracts in mathematics 107 .
<br/><br/><label>ISBN: </label>9780521440257 
<br/><br/><label>Dewey Class. No.: </label>6.08  / GHOU