1. Unidades biogeográficas de Colombia;Hernández,1991
2. Endemism in tropical versus temperate plant communities;Gentry,1986
3. Conserving the World’s Biological Diversity;MacNeely,1990
4. How many species inhabit the Earth?;May;Sci. Amer.,1992
5. World Atlas of Biodiversity, Earth’s Living Resources in the 21st Century;Groombridge,2002