W. C. Plowden: Travels in Abessinia and the Galla Country, with an account of a mission to Ras Ali in 1848. London 1868, Kapitel XIII, S. 259, auch S.264 ff.; Textarchiv – Internet Archive
jstor.org
Hooker: The Foreign Office and the ‘Abyssinian Captives’. In: Journal of African History, 2, 1961, S. 245; JSTOR:180000
