Sour, K.G. <br/><br/>
Publishers International ISBN Directory Vol. 2; Geographical Section R-Z. 

 - 29 
 - Berlin  International ISBN Agency  2002 
 - 1509-3018 
<br/><br/><label>ISBN: </label>3-598-21619-X 
<br/><br/><label>Universal Decimal Class. No.: </label>018.4(058)(100)  / SAU.2.02