Hopkins, D.P, <br/><br/>
Chemicals, Humus, and the Soil 

 - Chemical Publishing Co., Inc  N.Y.  1948 
 - 358p. 
<br/><br/><label>Nat. Bib. No.: </label>1638 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Agriculture
<br/><br/><label>Universal Decimal Class. No.: </label>631.8  / HOP