Wertz, V. R.  1882- <br/><br/>
Economic trends in agriculture / 
V. R. Wertz 
 - 3rd ed. 
 - Ann Arbor, Mich. :  J. W. Edwards,  c1954 
 - 409 p. :  ill. ;  23 cm. 
<br/><br/> Includes index 
<br/><br/><label>ISBN: </label> USD 4.50 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Agriculture--Economic aspects--United States
<br/><br/><label>Dewey Class. No.: </label>338.1