Johnston, Harry (1906). "Chapter XXV, Fauna: reptiles, amphibians, and fish". Liberia(PDF). London: Hutchinson & Co. pp. 807–808. ISBN1166209008. Retrieved 2023-05-09.
Johnston, Harry (1906). "Chapter XXV, Fauna: reptiles, amphibians, and fish". Liberia(PDF). London: Hutchinson & Co. p. 809. ISBN1166209008. Retrieved 2023-05-09. black and white illustration no. 306: Examples of the principal poisonous snakes of Liberia, (Rhinoceros puff-adder)