International patent classification 
/ WIPO 
 - Geneva:   WIPO,   1999 
 - 7th ed. .
<br/><br/>Vol. 3 (Section C: Chemistry; Metallurgy); ISBN: 92-805-0791-5; 281p. 
<br/><br/><label>ISBN: </label>92-805-0793-1 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Library science
<br/><br/><label>Subjects--Index Terms: </label>Patent classification 
<br/><br/><label>Universal Decimal Class. No.: </label>D 025.4PATENt N9