Electrically Operated Air Brake System, patent, August 25, 1908; (https://texashistory.unt.edu/ark:/67531/metapth509202/m1/1/: accessed July 18, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu; .
Electrically Operated Air Brake System, patent, August 25, 1908; (https://texashistory.unt.edu/ark:/67531/metapth509202/m1/1/: accessed July 18, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu; .