Cite

Courland, Livonia, Esthonia, GSGS 3696.

MLA

Section, Great Britain. War Office. General Staff. Geographical. Courland, Livonia, Esthonia, GSGS 3696. GSGS, War Office], 1918. https://collections.library.yale.edu/catalog/15475694.

APA, 6th edition

Section, G. B. W. O. G. S. G. (1918). Courland, Livonia, Esthonia, GSGS 3696. [Maps]. GSGS, War Office], https://collections.library.yale.edu/catalog/15475694.