Agricultural practices and water quality / 
edited by Ted L. Willrich and George E. Smith 
 - Ames :  Iowa State University Press,  1970 
 - xxvii, 415 p. :  ill. ;  24 cm. 
<br/><br/>Includes bibliographies. 
<br/><br/><label>ISBN: </label>0813817455 
<br/><br/><label>LCCN: </label>70-114798 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Water--Pollution<br/>Agriculture