Hempel E H <br/><br/>
Economics of chemical industries 
Hempel E H 
 -  1939 
<br/><br/><label>Source: </label> General Book 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Technologcal Industry
<br/><br/><label>Dewey Class. No.: </label>X9F::73:N5, G9