MLA

Sanborn Map Company, issuing body. Insurance Maps of Middletown, Middlesex County, Connecticut. 1907. https://collections.library.yale.edu/catalog/11139447.

APA, 6th edition

Sanborn Map Company, issuing body. (1907). Insurance maps of Middletown, Middlesex County, Connecticut. [Atlases, Cadastral maps, Connecticut, Fire insurance maps, local, Middletown]. https://collections.library.yale.edu/catalog/11139447.