Roddy, Dennis, 1931- Electronic communications / [by] Dennis Roddy, John Coolen. - 4th ed. - New Delhi: PHI Learning, 2009. - ix, 820 p. : ill. ; 26 cm. Includes index. ISBN: 9788120309845 LCCN: 94014041 Subjects--Topical Terms: Telecommunication. LC Class. No.: TK5101 / .R56 1995 Dewey Class. No.: 621.382