1. Wallace A. R., Tropical Nature and Other Essays (Macmillan, New York and London, 1878).
2. Morley R. J., Origin and Evolution of Tropical Rain Forests (Wiley, New York, 2000).
3. Flowering Plants
4. van der Pijl L., Dodson C., Orchid Flowers: Their Pollination and Evolution (Univ. of Miami Press, Coral Gables, FL, 1966).
5. Speciation in Amazonian Forest Birds