TY  - BOOK
AU  - Marcham,P
TI  - Data transmission via PABXs
SN  - 0850124549
U1  - TK/5105 
PY  - 1984///
CY  - Manchester, England
PB  - NCC Publication.
KW  - Data transmission systems.
KW  - Telephone -- private branch exchange.
KW  - Telephone, Automatic.
ER  -