Ecotourism in Costa Rica. Ecotourism in the less developed world: 79-108, 1998
The organization of ecotourism in Costa Rica. Acta Turistica 16(2): 143-168, 2004
Magnitude of ecotourism in Costa Rica and Kenya. Annals of Tourism Research 26(4): 792-816, 1999
An ecotourism assessment of Tortuguero, Costa Rica. Annals of Tourism Research 19(2): 367-370, 1992