Williams, S. E., Williams, Y. M., VanDerWal, J., Isaac, J. L., Shoo, L. P., & Johnson, C. N. (2009). Ecological specialization and population size in a biodiversity hotspot: How rare species avoid extinction. National Academy of Sciences.

Williams, S. E., Y. M. Williams, J. VanDerWal, J. L. Isaac, L. P. Shoo, e C. N. Johnson. Ecological Specialization and Population Size in a Biodiversity Hotspot: How Rare Species Avoid Extinction. National Academy of Sciences, 2009.

Williams, S. E., et al. Ecological Specialization and Population Size in a Biodiversity Hotspot: How Rare Species Avoid Extinction. National Academy of Sciences, 2009.