TY  - BOOK
AU  - Black 
TI  - Data networks : concepts, theory, and practice 
SN  - 0131984667 
U1  - 004.6 BLA 1989 
PY  - 1989///
CY  - Englewood Cliffs
PB  - Prentice Hall
KW  - Computer networks
KW  - Data transmission systems
N1  - Includes bibliographical references and index
ER  -