Graves, Robert P. <br/><br/>
Ground-water resources in Lajas Valley, Puerto Rico 
by Robert P. Graves. 
 - San Juan, P.R.  Department of the Interior  1991. 
 - vi, 55 p.  ill., maps 
 - Water resources investigations report  89-4182 .
<br/><br/><label>LCCN: </label>evl90007631  
<br/><br/><label>Subjects--Topical Terms: </label><br/>Geology--Puerto Rico--Lajas.<br/>Water supply--Puerto Rico--Lajas.
<br/><br/><label>Subjects--Geographic Terms: </label><br/>Puerto Rico
<br/><br/><label>Dewey Class. No.: </label>551.4/9