John Charles Walker <br/><br/>
Plant pathology 

 - New York  McGraw Hill Book Co.  1950 
 - 699p 
<br/><br/>John Charles Walker: Plant pathology.  New York.  McGraw Hill Book Co., 1950.--(632.3WAL)   
<br/><br/><br/>ENGLISH 
<br/><br/><label>Dewey Class. No.: </label>632.3  / WAL