Identifying sources of subsurface nitrate pollution with stable nitrogen isotopes / 
by Timothy J. Wolterink ... [et al.] 
 - Washington, D. C. :  United States Government Printing Office,  1979 
 - xi, 151 p. ;  28 cm. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Factory and trade waste<br/>Sewage--Purification
<br/><br/><label>Dewey Class. No.: </label>628.168