Ryan, John C. <br/><br/>
Life support :  conserving biological diversity / 
John C. Ryan. 
 - Washington, D.C. :  Worldwatch Institute,  c1992. 
 - 62 p. ;  22 cm. 
 - Worldwatch paper ;  108 .
 - Worldwatch paper .
<br/><br/> "April 1992." 
<br/><br/>Includes bibliographical references (p. 50-62). 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Proteção ambiental
<br/><br/><label>Dewey Class. No.: </label>301