Kolowski, J. M., Blake, S., Kock, M. D., Lee, M. E., Henderson, A., Honorez, A., et al. (2010). Movements of four forest elephants in an oil concession in Gabon, Central Africa. African Journal of Ecology, 48(4), 1134-1138. doi:10.1111/j.1365-2028.2009.01204.x.