Wetlands :  a threatenend landscape / 
edited by Michael Williams 
 - Oxford :  Basil Blackwell,  1990 
 - 419 p. :  ill. ;  25 cm. 
<br/><br/><label>ISBN: </label>0631166149 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Wetlands<br/>Wetland ecology<br/>Wetlands--Economic aspects<br/>Wetland conservation