TY  - BOOK
AU  - Kessler,Gary C.
TI  - ISDN: concepts, facilities, and services 
T2  - McGraw-Hill communications series
SN  - 0070342423
AV  - TK5103.7  .K47 1990
PY  - 1990///
CY  - New York
PB  - McGraw-Hill
KW  - Integrated services digital networks
ER  -