MLA

Sanborn Map Company, issuing body. Watertown, Litchfield County, Conn. 1906. https://collections.library.yale.edu/catalog/11676457.

APA, 6th edition

Sanborn Map Company, issuing body. (1906). Watertown, Litchfield County, Conn. [Atlases--Connecticut--Watertown--1906, Cadastral maps--Connecticut--Watertown--1906, Fire insurance maps--Connecticut--Watertown--1906]. https://collections.library.yale.edu/catalog/11676457.