MLA

Sanborn-Perris Map Co., issuing body. Insurance Maps of Hartford, Connecticut., Insurance Maps of Hartford, Connecticut: [New and Additional Sheets]. 0AD. https://collections.library.yale.edu/catalog/11687439.

APA, 6th edition

Sanborn-Perris Map Co., issuing body. (0 C.E.). Insurance maps of Hartford, Connecticut., Insurance maps of Hartford, Connecticut: [New and 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/11687439.