Troeh, Frederick R. & Thompson, Louis M. <br/><br/>
Soils and soil fertility.-6th ed. 

 - Iowa  Wiley  2005 
 - viii,489 
<br/><br/>
<br/><br/><br/>E 
<br/><br/><label>Dewey Class. No.: </label>631.4/Tro/Tho