Hawksworth, David L. <br/><br/>
Lichens as pollution monitors / 
David L. Hawksworth, Francis Rose. 
 - London :  Edward Arnold,  1976. 
 - 60 p. :  ill. ;  23 cm. 
 - The Institute of Biology's studies in biology ;  no. 66 .
<br/><br/><label>ISBN: </label>0713125543 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Lichens<br/>Plants, Effect of air pollution on.