Fenner, Ferdinand A. & Power, John H. Improvement in Apparatus for Destroying the Cutting Ant., patent, August 3, 1875; (https://texashistory.unt.edu/ark:/67531/metapth166461/m1/1/: accessed June 20, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .