TY  - BOOK
AU  - Black,Uyless D.
TI  - Data networks: concepts,theory and practice 
SN  - 013198599x (pbk. ) 
PY  - 1989///
CY  - London
PB  - Prentice-Hall International
KW  - Computers
KW  - Network
N1  - Includes bibliographical references.; Includes index
ER  -