Smith, Richard A.,  1945- <br/><br/>
A study of trends in total phosphorus measurements at NASQAN stations / 
by Richard A. Smith, Robert M. Hirsch, and James R. Slack 
 - Washington, D.C. :  United States Geological Survey,  1982 
 - iv, 34 :  ill. ;  29 cm. 
 - Geological Survey water-supply paper ;  no. 2190 .
<br/><br/>Bibliography: p. 34 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Water--Phosphorus content<br/>Water quality
<br/><br/><label>Dewey Class. No.: </label>363.7394