Krapf, J.L. 1860. Travels, researches, and missionary labours, during an eighteen years' residence in Eastern Africa. Together with journeys to Jagga, Usambara, Ukambani, Shoa, Abessinia, and Khartum, and a coasting voyage from Mombae to Cape Delgado. London, Trubner and Co: vol. 1.