Roark, R. C <br/><br/>
The history of the use of derris as an insecticide  / 
by R. C. Roark 
 - Washington  :   Department of Agriculture 
 - 79 p. 
 - EUA. Dep. of Agri. E-468 .
<br/><br/><label>LCCN: </label>202866 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Derris como insecticida