TY  - BOOK
AU  - Bush,Stanley E.
AU  - Parsons,Charles R.
TI  - Private branch exchange systems and applications
SN  - 0070097062
PY  - 1993///
CY  - New York
PB  - McGraw-Hill.
KW  - Telephone
KW  - Private branch exchange
N1  - Includes index
ER  -