Shelly, Gary B. <br/><br/>
Business data communications :  introductory concepts and techniques / 
Gary B. Shelly, Thomas J. Cashman and  Judy A. Serwatka. 
 - 4th ed. 
 - Cambridge, Mass. ;  London :  Course Technology,  2004. 
 - xv, [various]p. :  col. ill. 
 - Shelly Cashman series.  Introductory .
<br/><br/> Previous ed.: 2001. 
<br/><br/><label>ISBN: </label>0789568063 
<br/><br/><label>Nat. Bib. No.: </label>GBA3-U0966 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Data transmission systems.<br/>Computer networks.<br/>Data transmission systems.<br/>Computer networks.