TY  - GEN
AU  - Froman,Nanny
AU  - Froman,Olof
TI  - Physical problems solved by the phase integral method
SN  - 9780521812092
U1  - 530.124 
PY  - 2002///
CY  - Cambridge
PB  - Cambridge Univesity Press
KW  - WKB approximation
KW  - Wave equation
ER  -