TY  - BOOK
AU  - Bogoliubov N N
AU  -  Mitropolsky Y A
TI  - Asymptotic methods in the theory of non-linear osc
T2  - International monographs on Advanced Mathematics and Physics
U1  - BObD, K1 
PY  - 1961///
CY  - Russian.Ed2
PB  - Hindustan Publishing         
KW  - Mathematics
N1  - Bibliography P535-37
ER  -