MLA

Sanborn-Perris Map Co., issuing body. Insurance Maps of Hartford, Connecticut., Insurance Maps of Hartford, Connecticut: [Additional Sheets]. 1916. https://collections.library.yale.edu/catalog/11687438.

APA, 6th edition

Sanborn-Perris Map Co., issuing body. (1916). Insurance maps of Hartford, Connecticut., Insurance maps of Hartford, Connecticut: [Additional sheets]. [Atlases--Connecticut--Hartford--1900, Atlases--Connecticut--West Hartford--1900, Cadastral maps--Connecticut--Hartford--1900, Cadastral maps--Connecticut--West Hartford--1900, Fire insurance maps--Connecticut--Hartford--1900, Fire insurance maps--Connecticut--West Hartford--1900]. https://collections.library.yale.edu/catalog/11687438.