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Fontaine B., Bouchet P., Van Achterberg K., Alonso-Zarazaga M. A., Araujo R. et al. (2007). "The European union’s 2010 target: Putting rare species in focus." Biological Conservation139: 167-185. Table 2 on the page 173. doi:10.1016/j.biocon.2007.06.012. PDF.