Beebe, Spencer B. <br/><br/>
The international program :   A progress report. 

 - New York-US :   The nature conservancy,   1986. 
 - páginas 4-6 :   ilustraciones full color 
 - Irregular 
 - Vol. 36, no.1 (Jan/Mar 1986) 
 - The nature conservancy news ;   no.1 .
 - The nature conservancy news. .