Roddy, Dennis, 1931- Electronic communications / [by] Dennis Roddy, John Coolen. - 4th ed. - Englewood Cliffs, NJ : Prentice Hall Career and Technology, c1995. - ix, 820 p. : ill. ; 26 cm. Includes index. ISBN: 013312083X LCCN: 94014041 Subjects--Topical Terms: Telecommunication. LC Class. No.: TK5105 / .R61 1995 Dewey Class. No.: 621.382