フレデリックスバーグ郡区 (アイオワ州チカソー郡)
↑ Fairbairn, Robert Herd (1919). History of Chickasaw and Howard Counties, Iowa, Volume 1. S. J. Clarke Publishing Company. pp. 265. https://books.google.com/books?id=n4QUAAAAYAAJ&pg=PA265#v=onepage&q&f=false