1. Applequist WL (2011) Catharanthus roseus (L.) G. Don. Encyclopedia of Life. Available at http://www.eol.org/pages/581125. Accessed July 2, 2011.
2. Biodiversity hotspots house most undiscovered plant species
3. Biodiversity hotspots for conservation priorities
4. US and Vietnam plan joint dioxin research
5. Sciencewatch.com (2008) The 20 Most Cited Papers in Environment & Ecology, 1998–2008, Available at http://sciencewatch.com/inter/aut/2008/08-oct/08oct20PaprsENV/. Accessed July 2, 2011.