Planned Change in Farming Systems: Progress in On-Farm Research 

 - New York  John Wiley & Sons  1991 
 - 348p 
<br/><br/><label>ISBN: </label>0471934178 
<br/><br/><label>LCCN: </label>nam a22     7a 4500 
<br/><br/><label>Dewey Class. No.: </label>630.72/PLA/1991