Cite

Congo State. Levels along lines of projected railways from the Upper Congo to Albert Nyanza and Tanganyika [cartographic material] / from Belgian official surveys.

MLA

Congo State. Levels along Lines of Projected Railways from the Upper Congo to Albert Nyanza and Tanganyika [Cartographic Material] / from Belgian Official Surveys. Royal Geographical Society, 1908. https://collections.library.yale.edu/catalog/15533531.

APA, 6th edition

Congo State. Levels along lines of projected railways from the Upper Congo to Albert Nyanza and Tanganyika [cartographic material] / from Belgian official surveys. (1908). [Maps]. Royal Geographical Society, https://collections.library.yale.edu/catalog/15533531.