TY  - BOOK
AU  - Smith,Sydney F.
TI  - Telephony and telegraphy A: an introduction to instruments and exchanges (step-by-step and common control) 
SN  - 0198593465
PY  - 1974///
CY  - London
PB  - Oxford University Press
KW  - Communication engineering
KW  - Telecommunication systems
KW  - Telephone sysytems
KW  - Telegraph
ER  -