Johnston, P. M.  1904-1989. <br/><br/>
Ground-water supplies in shale and sandstone in Fairfax, Loudoun, and Prince William Counties, Virginia. 

 - Washington,  [U.S. Geological Survey]  1960. 
 - iv, 7 p.  map, tables.  27cm. 
<br/><br/> Errata slip inserted. 
<br/><br/>Bibliography: p. 6-7. 
<br/><br/><label>LCCN: </label>gs 60000226  
<br/><br/><label>Subjects--Topical Terms: </label><br/>Water-supply--Virginia.<br/>Groundwater--Virginia.<br/>Borings--Virginia.<br/>Water--Composition.<br/>Geology--Virginia.<br/>Geology, Stratigraphic--Triassic.
<br/><br/><label>LC Class. No.: </label>QE75  / .C5 no. 424