MLA

Sanborn Map Company, issuing body. Insurance Maps of Ansonia, Connecticut, New Haven County. 1911. https://collections.library.yale.edu/catalog/11021553.

APA, 6th edition

Sanborn Map Company, issuing body. (1911). Insurance maps of Ansonia, Connecticut, New Haven County. [Atlases, Cadastral maps, Connecticut, Fire insurance maps, local]. https://collections.library.yale.edu/catalog/11021553.