TY  - GEN
AU  - Held,Gilbert
TI  - Understanding data communications
SN  - 8120310802
U1  - 621.3811 
PY  - 1994///
CY  - New Delhi
PB  - Prentice-Hall of India
KW  - Data communication
KW  - Multiplexing techniques
KW  - Protocols
ER  -