Black, Uyless Data networks: concepts, theory and practice / Uyless Black -- Englewood Cliffs, NJ : Prentice--Hall, 1989 xvi, 877 p. 22 cm. Includes bibliographical references and index. ISBN: 9718636358 Subjects--Topical Terms: Data transmission systems.Dewey Class. No.: GC 004.6 B561 1989