Kahl, M.P. & B.D. Armstrong. 2000. Visual and tactile displays in African elephants, Loxodonta africana: A progress report (1991-1997). Elephant 2 (4): p. 19-21.

Poole, J.H. and Granli, P.K. Signals, gestures and behaviors of African elephants. In: The Amboseli Elephants: A Long-Term Perspective on a Long-Lived MammalMoss, C.J., Croze, H.J & Lee, P.C. (Eds.) University of Chicago Press.

Rasmussen, L.E.L. & B. Munger. 1996. The sensorimotor specializations of the trunk tip of the Asian elephant, Elephas maximus. The Anatomical Record 246:127-134.

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