Triple Valve For Air-Brakes, patent, August 25, 1903; (https://texashistory.unt.edu/ark:/67531/metapth510383/m1/1/: accessed June 20, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .
Triple Valve For Air-Brakes, patent, August 25, 1903; (https://texashistory.unt.edu/ark:/67531/metapth510383/m1/1/: accessed June 20, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .