Input- output bibliography 1966-70 

 - New York  United Nations          1972 
 - x, 344p  cm. 
 - Series no. 55 .
<br/><br/> Statistical papers 
<br/><br/><label>Source: </label> General Book 
<br/><br/><label>Dewey Class. No.: </label>V1N45,93:8.N70-N66, L2 /UN