Ashworth, William  1942- <br/><br/>
The encyclopedia of environmental studies / 
William Ashworth 
 - New York :  Facts on File,  1991 
 - viii, 470 p. :  ill. , maps ;  29 cm. 
<br/><br/>Bibliography : p. 435-440 Includes index 
<br/><br/><label>ISBN: </label>0816015317 
<br/><br/><label>LCCN: </label>89-048425 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Ecology--Dictionaries<br/>Environmental protection--Dictionaries<br/>Environmental Protection--United State--Dictionaries