Moiseiwitsch B L <br/><br/>
Variational principles 

 -  1966 
 - p.  cm. 
 - Interscience monographs and texts in physics and astronomy; 20 .
<br/><br/><label>Standard No.: </label>29679 
<br/><br/><label>Source: </label> Standards 
<br/><br/><label>Dewey Class. No.: </label>B42, K6