Phosphorus for agriculture  
/ The potash & phosphate institute  
 -  The Potash & Phosphate Institute  
<br/><br/><label>Subjects--Topical Terms: </label><br/>Agriculture 
<br/><br/><label>Subjects--Index Terms: </label>Plants  Nitrogenre 
<br/><br/><label>Universal Decimal Class. No.: </label>631  / M8