Elsgolts, L. E. <br/><br/>
Differential equations and the calculus of variations / 
by L. Elsgolts. Translated from the Russian by George Yankovsky 
 - Moscow :  Mir,  1970 
 - 440 p. ;  22 cm. 
<br/><br/> Translation of Differentsialnye uravneniia i variatsionnoe ischislenie. 
<br/><br/>Bibliography: p. 436 
<br/><br/><br/>engrus 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Differential equations<br/>Calculus of variations