World heritage twenty years later : based on papers presented at the World Heritage and other workshops held during the IVth World Congr ess on National Parks and Protected Areas, Caracas, Venezuela, February 1992 - Thorsell, J. W.; Sawyer, Jacqueline; International Union for conservation of nature and natural resources .; World Heritage Committee; World Congress on National Parks and Protected Area 199 2 : Caracas, Venezuela) (Gland, Switzerland : IUCN, the World Conservation Union, in colla boration with UNESCO's World Heritage Committee, 1992)
Keywords: Natural areas -- Congresses; National parks and reserves -- Congresses