Tinbergen J Ed. <br/><br/>
Observations on the planned provisison of nitrogen 

 -  1956 
 - 45p  cm. 
<br/><br/><label>Source: </label> General Book 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Soil Industry
<br/><br/><label>Dewey Class. No.: </label>X9(J:24).1-1, J6