MLA

Sanborn Map Company, issuing body. Insurance Maps of Mystic, Including Old Mystic and West Mystic, New London County, Connecticut. 1911. https://collections.library.yale.edu/catalog/11140079.

APA, 6th edition

Sanborn Map Company, issuing body. (1911). Insurance Maps of Mystic, including Old Mystic and West Mystic, New London County, Connecticut. [Atlases, Cadastral maps, Connecticut, Fire insurance maps, local, Mystic]. https://collections.library.yale.edu/catalog/11140079.