TY  - BOOK
AU  - Berg Lothar
TI  - Introduction to the operational calculus
T2  - Applied mathematics and mechanics; 2
U1  - B48, K71 
PY  - 1967///
CY  - Amsterdam
PB  - North Holland        
KW  -  Finite difference
KW  -  REF calculus
KW  - Mathematics
ER  -