TY  - BOOK
AU  - Elsgolts, L.
AU  - Yankovsky, George
TI  - DIFFERENTIAL EQUATIONS AND THE CALCULUS OF VARIATIONS
U1  - 515.3 
PY  - 1970///
CY  - Moscow
PB  - Mir Publishers
KW  - Differential Equations
KW  - Calculus Of Variations
ER  -