TY  - GEN
AU  - Johnson, David E., 
TI  - Introduction to filter theory
T2  - Prentice-Hall electrical engineering series
SN  - 0134837762
AV  - TK7872.F5 
U1  - 621.3815/32 
PY  - 1976///
CY  - Englewood Cliffs, N.J.
PB  - Prentice-Hall
KW  - Electric filters
N1  - Includes index; Bibliography: p. 283-286
ER  -