Tromp, S. W.  1909- <br/><br/>
Development of Geological resources in El Salvador / 
prepared by the Government of El Salvador by S. W. Tromp, expert appointed by the Technical Assistance Programme 
 - New York :  United Nations,  1954 
 - iv, 100 p. :  ill. ;  27 cm. 
<br/><br/>Bibliography : p. 83-100 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Geology--El Salvador
<br/><br/><label>Dewey Class. No.: </label>333.7