Hobbs, Marvin <br/><br/>
Modern communications switching systems / 
Marvin Hobbs 
 - 2nd ed. 
 - Blue Ridge Summit, Pa.  Tab Books  1981 
 - 308p.  ill.  22cm. 
<br/><br/>Includes index 
<br/><br/><label>ISBN: </label>0830696350  RM33.85 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Telephone switching systems, Electronic<br/>Telephone, Automatic