Gould, S. H. <br/><br/>
Variational methods for eigenvalue problems; an introduction to the Weinstein method of intermediate problems  / 

 - 2nd 
 - Canada:  University of Toronto Press,  1966 
 - xvi, 275p. Index 
 - Mathematical Expositions   no. 10 .
<br/><br/><label>Dewey Class. No.: </label>517  / G698.VM