Great Britain. Directorate of Overseas Surveys, Institute of Geological Sciences (Great Britain), & Vail, J. R. (1975). The Democratic Republic of Sudan and adjacent areas, geological map. The Directorate.
Chicago Style (17th ed.) CitationGreat Britain. Directorate of Overseas Surveys, Institute of Geological Sciences (Great Britain), and J. R. Vail. The Democratic Republic of Sudan and Adjacent Areas, Geological Map. [Tolworth, Surrey]: The Directorate, 1975.
MLA (9th ed.) CitationGreat Britain. Directorate of Overseas Surveys, et al. The Democratic Republic of Sudan and Adjacent Areas, Geological Map. The Directorate, 1975.
Warning: These citations may not always be 100% accurate.