Heldman, Robert K. <br/><br/>
ISDN in the information marketplace /  [Book]. 
Robert K. Heldman.  
 - 1st ed. 
 - Blue Ridge Summit, PA :   Tab Professional and Reference Books,   1988. 
 - xv, 333 p. :   ill. ;   25 cm. 
<br/><br/> Includes index. 
<br/><br/>Bibliography: p. 306-325. 
<br/><br/><label>ISBN: </label>0830693157 
<br/><br/><label>LCCN: </label>88001891 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Integrated services digital networks.