Economic Values of Protected Areas :  guidelines for protected area managers / 
World  Commission on Protected Areas. 
 - Cambridge:  IUCN Publications Services Unit,  1998. 
 - 52 p.:  30 cm. 
<br/><br/><br/>Ingles 
<br/><br/><label>ISBN: </label>2831704618  Normal 
<br/><br/><label>Dewey Class. No.: </label>333.71