Station-Indicator, patent, October 23, 1888; (https://texashistory.unt.edu/ark:/67531/metapth171880/m1/1/: accessed June 22, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .
Station-Indicator, patent, October 23, 1888; (https://texashistory.unt.edu/ark:/67531/metapth171880/m1/1/: accessed June 22, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .