TY  - BOOK
AU  - Black,Uyless
TI  - Data networks : concepts, theory, and practice 
SN  - 0131984667 (hardcover)
PY  - 1989///
CY  - Englewood Cliff
PB  - Prentice Hall
UR  - http://www.amazon.com/exec/obidos/ASIN/0131984667/chopaconline-20
ER  -