Roddy, Dennis. Electronic communications / Dennis Roddy and John Coolen. - 4th ed. - New Delhi : Pearson/Prentice Hall , c2008 [Impression 2009]. - ix, 723 pages : illustrations ; 26 cm. Includes index. ISBN: 9788177585582 Subjects--Topical Terms: Telecommunication. Dewey Class. No.: 621.382 ROD