Trapnell, C. G. (1972). Vegetation-soil map of Northern Rhodesia: D.O.S. 3012 (Partially redrawn and photographed by Directorate of Overseas Surveys 1962.). Ordnance Survey.
Chicago-Zitierstil (17. Ausg.)Trapnell, Colin Graham. Vegetation-soil Map of Northern Rhodesia: D.O.S. 3012. Partially redrawn and photographed by Directorate of Overseas Surveys 1962. Tolworth, England: Ordnance Survey, 1972.
MLA-Zitierstil (9. Ausg.)Trapnell, Colin Graham. Vegetation-soil Map of Northern Rhodesia: D.O.S. 3012. Partially redrawn and photographed by Directorate of Overseas Surveys 1962. Ordnance Survey, 1972.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.