TY  - BOOK
AU  - Bates, Regis J.
TI  - Principles of Voice and Data Communication /Regis J. Bates, Marcus Bates
SN  - 13: 9780072257328
U1  - 621.382BAT 
PY  - 2007///
CY  - Boston
PB  - Mc Graw- Hill
ER  -