TY  - BOOK
AU  - CCITT
TI  - BLUE BOOK,VOLUME III,FASCICLE III.5: DIGITAL NETWORKS,DIGITAL SECTIONS AND DIGITAL LINE SYSTEMS RECOM
SN  - ERNET
U1  - 335 
PY  - 1989///
CY  - GENEVA
PB  - ITU
N1  - SC-021
ER  -