W. & A.K. Johnston's map to illustrate the Transvaal question.
MLA
W., and A. K. Johnston Limited. W. & A.K. Johnston's Map to Illustrate the Transvaal Question. W. & A.K. Johnston, 0AD. https://collections.library.yale.edu/catalog/15533489.
APA, 6th edition
W., & Limited, A. K. J. (0 C.E.). W. & A.K. Johnston's map to illustrate the Transvaal question. [Maps]. W. & A.K. Johnston, https://collections.library.yale.edu/catalog/15533489.