Ashworth, William. <br/><br/>
The encyclopedia of environmental studies / 
William Ashworth. 
 - New York :  Facts on File,  1991. 
 - 470 p. :  ill., maps. 
<br/><br/>Includes bibliographical references. 
<br/><br/><label>ISBN: </label>0816015317 (hardbound : acid-free paper) :  $60.00  ($75.00 Canada) 
<br/><br/><label>LCCN: </label>89048425 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Ecology--Dictionaries.<br/>Environmental protection--Dictionaries.<br/>Pollution--Dictionaries.
<br/><br/><label>Dewey Class. No.: </label>333.7