Helgeson, Earl Adrian. <br/><br/>
Methods of weed control. 

 - Rome :    Food and Agriculture Organization of the United Nations,    1957. 
 - x, 189 p. :    ill. ;    23 cm. 
 - FAO agricultural studies ;    no. 36 .
<br/><br/>Includes bibliographical references (p. 155-158). 
<br/><br/><label>Subjects--Topical Terms: </label><br/> Weeds -- Control.