Shrader, Robert L. <br/><br/>
Electronic communication/ 
Robert L. Shrader 
 - 4th ed. 
 - United State :  McGraw Hill Publishing,  1980 
<br/><br/><label>ISBN: </label>70571503 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Electronic communication
<br/><br/><label>Dewey Class. No.: </label>621.38  / SHR