00729nac a22002171u 4500 99060971 8176353191 0672322161 004.6 H4743 429 429 Held, Gilbert, Understanding data communications / Gilbert Held. 7th ed. Boston : Addison; 2002. xviii, 765 p. : ill. ; 24 cm. Previous eds. written by George E. Friend ... et al. Data transmission systems. Computer networks. BB 004.6H4743 429 429 0 0 ddc 0 0 MAIN MAIN LOW 2006-05-16 purchase 70.00 0 004.6 HEL 000004196 2025-07-15 00:00:00 87.50 BB