TY  - BOOK
AU  - Helgert,Hermann J.
TI  - Integrated services digital networks: architectures, protocols, standards 
SN  - 0201525011
PY  - 1991///
CY  - Reading, Mass. : 
PB  - Addison-Wesley, 
KW  - Integrated services digital networks
N1  - Includes bibliographical references (p. 430-441) and index
ER  -