%0 Book %A Shelly, Gary B. %E Serwatka, Judy A. %E Cashman, Thomas J. %I Course Technology %D 2001 %C Boston %@ 0789559587 %T Business data communications : introductory concepts and techniques / Gary B. Shelly, Thomas J. Cashman [and] Judy A. Serwatka.. %7 3rd ed..