An american national standard  : IEEE recommended practice for the design of reliable indusrial and commercial power systems 
/ American national standards institute 
. - New York  : IEEE, 1980
. - 224 p.  ; 26 cm. 
 - The IEEE Gold book .
<br/><br/>Bibliogr. 
<br/><br/><label>ISBN: </label>0471092614 
<br/><br/><label>Source: </label> Don 
<br/><br/><label>Universal Decimal Class. No.: </label>621.313.