Universal Decimal Classification :  UDC 5/50 exact sciences in general, nature study, conservation 

 - 2. ed 
 - 14 p. 
 - FID publication ; n.483 .
<br/><br/><label>ISBN: </label>0-580-08004-5 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Matemática
<br/><br/><label>Universal Decimal Class. No.: </label>025.45CDU  / F293u