TY  - BOOK
AU  - Heldman, Robert K.
TI  - Information Telecommunications. Networks, Products, & Services / Robert K. Heldman
SN  - 0-07-028040-1
AV  - HE7631 H474 
U1  - 384 H762i 
CY  - Estados Unidos : McGraw-Hill, Inc.
ER  -