Martin, John H.  1893- <br/><br/>
Principles of field crop production / 
John H. Martin, Warren H. Leonard. 
 - 2nd ed. 
 - New York :  Macmillan,  1967. 
 - ix,1044 p. :  ill. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Field crops--United States.