Keys to small organisms on soil, litter, and water troughs 

 - London  Penguin Books Ltd. England        1966 
 - 26p.  cm. 
<br/><br/><label>Standard No.: </label>89414 
<br/><br/><label>Source: </label> Textbook 
<br/><br/><label>Subjects--Topical Terms: </label><br/>BIOLOGY
<br/><br/><label>Dewey Class. No.: </label>G958, K6