The encroaching desert : 

 - Harare :  College Press,  c1990 
 - 132 p. : 
<br/><br/> Includes bibliographical references  and index 
<br/><br/><label>ISBN: </label>0869257021 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Desertification.<br/>Arid regions agriculture.
<br/><br/><label>Dewey Class. No.: </label>333.736