United States. Post Office Dept. "Post route map of the states of Illinois, Iowa, and Missouri with adjacent parts of Indiana, Wisconsin, Minnesota, Nebraska, Kansas and Arkansas showing post offices with the intermediate distances and mail routes in operation on the 1st of October 1891." Map. Washington, D.C.: Post Office Dept., 1891. Norman B. Leventhal Map & Education Center, https://collections.leventhalmap.org/search/commonwealth:cj82kj811 (accessed April 24, 2024).