Gray, N. F. <br/><br/>
Biology of wastewater treatment / 
N.F. Gray 
 - 2nd ed. 
 - London :  Imperial College Press,  2004 
 - xviii, 1421 p. :  ill. ;  23 cm. 
 - Series on enviromental science and management ;  vol. 4 .
<br/><br/><label>ISBN: </label>1860943284 1860943322 (pbk.) 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Sewage--Purification--Biological treatment<br/>Sewage disposal<br/>Biotechnology
<br/><br/><label>National Library of Medicine Call No.: </label>WA778