TY  - BOOK
AU  - Penfold, R. A.
AU  - Penfold, R. A.
TI  - Electronic security devices
SN  - 9780900162763
AV  - 621.38928 PEN 1979 
U1  - 621.38928 PEN 1979 
PY  - 1979///
CY  - London
PB  - Babani
KW  - Electronic Engineering
ER  -