MLA

Wilson, James, Jr. General Map of the Lead Region Showing the Distribution of the Lodes / by James Wilson, Jr. Wisconsin Geological Survey, 1880. https://collections.library.yale.edu/catalog/15814558.

APA, 6th edition

Wilson, J., Jr. (1880). General map of the lead region showing the distribution of the lodes / by James Wilson, Jr. [Maps]. Wisconsin Geological Survey, https://collections.library.yale.edu/catalog/15814558.