MLA

Sanborn-Perris Map Co., issuing body. Greenwich, Fairfield Co., Conn. 1891. https://collections.library.yale.edu/catalog/11128859.

APA, 6th edition

Sanborn-Perris Map Co., issuing body. (1891). Greenwich, Fairfield Co., Conn. [Atlases--Connecticut--Greenwich (Town)--1891.--local, Cadastral maps--Connecticut--Greenwich (Town)--1891.--local]. https://collections.library.yale.edu/catalog/11128859.