Helgesen, John O. <br/><br/>
Hydrology of the Great Plains aquifer system in Nebraska, Colorado, Kansas, and adjacent areas / 
by John O. Helgesen, Robert B. Leonard and Ronald J. Wolf. 
 - Washington:   United States Government Printing Office,   1993.  
 - viii, E80 p. :  maps, tables ;  29 cm. 
 - Regional aquifer-system analysis : Central MidwestChapter E Geological Survey Professional PaperChapter E  1414 .
<br/><br/>Includes bibliographical references (p. E77-E80). 
<br/><br/><label>Subjects--Geographic Terms: </label><br/>High Plains Aquifer
<br/><br/><label>Dewey Class. No.: </label>551.490978