Spedding, Colin Raymond Willian. <br/><br/>
An introduction to agricultural systems 

 - London :  Applied Science,  1979 
 - 189 p.  : ilus. 
<br/><br/><label>LCCN: </label>57791 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Ecología agrícola.<br/>Ecosistema.<br/>Sistemas de cultivo.
<br/><br/><label>Dewey Class. No.: </label>630.215  / S63