TY  - BOOK
AU  - Fröman,Nanny
AU  - Fröman,Per Olof
TI  - JWKB approximation: contributions to the theory 
U1  - 530.12 20
PY  - 1965///
CY  - Amsterdam
PB  - North-Holland Pub. Co.; [sole distributors for U.S.A.: Interscience Publishers, New York]
KW  - Perturbation (Quantum dynamics)
N1  - Includes bibliography and index
ER  -