William Ryan and Walter Pitman, Noah's Flood, 1999, ISBN 0-684-85920-3 NealAscherson, Black Sea (Vintage 1996), ISBN 0-09-959371-8 Schmitt, Rüdiger. Black
ISBN 978-0-333-69872-3. 请检查|isbn=值 (帮助). Hochschild 61–67. Hochschild 84–87. Ascherson, Neal (1963), The King Incorporated, Leopold the Second and the Congo, London: