MLA

Howell, Reading, 1743-1827. A map of the state of Pennsylvania / [cartographic material] / by Reading Howell, MDCCCXI ; engraved by J. Vallance.. BRBL_00498. 1811. https://collections.library.yale.edu/catalog/15790125.

APA, 6th edition

Howell, Reading, 1743-1827. (["BRBL_00498"])(1811)[A map of the state of Pennsylvania / [cartographic material] / by Reading Howell, MDCCCXI ; engraved by J. Vallance.]. https://collections.library.yale.edu/catalog/15790125.