Estes, A. B., Kümmerle, T., Kushnir, H., Radeloff, V. C., Shugart, H. H. (2012): Land-cover change and human population trends in the greater Serengeti ecosystem from 1984-2003. - Biological Conservation, 147, 1, 255-263.https://doi.org/10.1016/j.biocon.2012.01.010