International patent classification 
/ WIPO 
 - Geneva:   WIPO,   1994 
 - 7th ed. .
<br/><br/>Vol. 9 (Guide, survey of classes and summary of main groups); ISBN: 92-805-0510-6; 313p. 
<br/><br/><label>ISBN: </label>92-805-0510-6 
<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 N4.9