TY  - BOOK
AU  - Bogolyubov,N.N & Mitropolskii,YuA
ED  - Mitropolskii, Yu.A
TI  - Asymptotic methods to theory of non-linear oscillations
U1  - 6.06+4.04 
PY  - 1963///
CY  - Moscow
PB  - Physico Math. Literature
N1  - Russian
ER  -