Labour- Saving Ideas 

 - Food and Agriculture Organization of the United Nations.   Rome  1974 
 -  Fig. 
 - Volume  6 .
<br/><br/><label>ISBN: </label>92-5-000267-X 
<br/><br/><label>Nat. Bib. No.: </label>6634 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Management & Public Relations
<br/><br/><label>Universal Decimal Class. No.: </label>650  / LAB