Provisional central product classification. 

 - New York :    United Nations,    1991. 
 - viii, 296 p. ;    28 cm. 
 - Statistical papers.    Series M ;    no. 77 .
<br/><br/>Includes bibliographical references. 
<br/><br/><label>ISBN: </label>9211613299 
<br/><br/><label>Subjects--Topical Terms: </label><br/> Commercial products -- Classification.