MLA

Sanborn Map Company, cartographer. Elmore, Ottowa County Ohio. Sanborn Map Company, 0AD. https://collections.library.yale.edu/catalog/16372758.

APA, 6th edition

Sanborn Map Company, cartographer. (0 C.E.). Elmore, Ottowa County Ohio. [Cadastral maps., Fire insurance maps.]. Sanborn Map Company, https://collections.library.yale.edu/catalog/16372758.