Elsgolts, L.  <br/><br/>
Differential equations and the calculus of variations / 
L. Elsgolts ; translated by George Yankovosky. 
 - Moscow :  Mir publishers,  c1977. 
 - 440 pages :  illustrations ;  22 cm. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Differential equations.
<br/><br/><label>Dewey Class. No.: </label>515.35 ELS