Talley, David Basic carrier telephony/ David Talley - 2nd rev. ed. - Bombay: D.B. Taraporevala, c1980 - v, 198 p.; 21 cm. Includes index ISBN: $ 6.85 Subjects--Topical Terms: TelephoneTelephone systemsTelephone, carrier currentElectric filters Dewey Class. No.: 621.385