Odom, Wendell CISCO CCNA Exam 640-507 Certification Guide - New Delhi Techmedia 2000 - xxiv, 818p. p. ISBN: 81-7635-445-7 Subjects--Topical Terms: Oprrating System-fundametals ;Layered communication ;CCNA ;Examination Certification Dewey Class. No.: 004.6 / ODO