TY  - BOOK
AU  - Roger L.Freeman
TI  - Practical data communications 
SN  - 0-471-39273-1
AV  - FCM TK5705.F72 
PY  - 2001///
CY  - New York
PB  - :Wiley-Interscience Publications
KW  - Data transmission systems
N1  - Includes index
ER  -