Bellamy, John.
Digital telephony - 2nd ed. - New York John wiley & sons 1991 - xix, 572 p. - Wiley series in telecommunications .
0-471-62056-4
Digital telephony
621.385 / BEL
Digital telephony - 2nd ed. - New York John wiley & sons 1991 - xix, 572 p. - Wiley series in telecommunications .
0-471-62056-4
Digital telephony
621.385 / BEL