Environmental microbiology / 
Ian L. Pepper, Charles P. Gerba, Terry J. Gentry. 
 - Third edition. 
 - xxii, 705 pages : 
<br/><br/><label>ISBN: </label>9780123946263 0123946263 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Microbial ecology.