Kristaly, Alexandru <br/><br/>
Variation principles in mathematical physics,geometry, and economics: Qualitative Analysis of Nonlinear Equations and unilateral problems 

 - 1st 
 - Cambridge  Cambridge university press  2010 
 - xv,368p p. 
<br/><br/><label>ISBN: </label>978-0-521-11782-1 
<br/><br/><label>Subjects--Index Terms: </label>Calculus of variations;