Webb, John W. <br/><br/>
Programmable logic controllers :   principles and applications / 
John W. Webb, Ronald A. Reis 
 - 4th ed. 
 - Upper Saddle River, NJ:   Prentice Hall,   1999 
 - xv, 443 p.:   ill.;   24 cm. 
<br/><br/>Includes bibliographical references (p. 435-437) and index 
<br/><br/><label>ISBN: </label>0136794084 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Programmable controllers