Shelly, Gary B., Business data communications : introductory concepts and techniques / Gary B. Shelly, Thomas J. Cashman, Judy A. Serwatka. - 1 volume (various pagings) ; colour illustrations, colour maps ; 28 cm. - Shelly Cashman series . - Shelly Cashman series. . Previous edition : 2001. Includes bibliographical references and index. ISBN: 9780789568069 (paperback) Hadiah Subjects--Topical Terms: Data transmission systems.