TY  - BOOK
AU  - Kessler,Gary C
TI  - ISDN: : Concepts, facilities, and services
SN  - 0-07-034242-3
PY  - 1990///
CY  - New York: 
PB  - McGraw-Hill Inc, 
KW  - ISDN
KW  - ISDN services
ER  -