Welch, E. B. <br/><br/>
Ecological effects of waste water / 
E. B. Walch with hydrographic characteristics by T. Lindell 
 - Cambridge :  Cambridge University Press,  1980 
 - 337 p. ; 25 cm. 
<br/><br/>Includes bibliographical references and index 
<br/><br/><label>ISBN: </label>0521224950 0521295254 (pbk.) 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Sewage--Environmental aspects