International Electrotechnical Commission <br/><br/>
IEC: 60947-5-1 (Amendement 2) - 1999; Low -- Voltage switchgear and controlgar-- part 5-1: Control circuit and switching elements-- Electromechanical control circuit devices 

 - Geneva  IEC  1999 
 - 9 
<br/><br/><label>ISBN: </label>2-8318-4990-X 
<br/><br/><label>Universal Decimal Class. No.: </label> /