United States. Post Office Dept. "Post route map of the states of Pennsylvania, New Jersey, Delaware, and Maryland and of the District of Columbia with adjacent parts of New York, Ohio, Virginia, and West Virginia." Map. Washington: Post Office Dept., 1891. Norman B. Leventhal Map & Education Center, https://collections.leventhalmap.org/search/commonwealth:cj82kk087 (accessed April 19, 2024).