Door Opener, patent, June 8, 1915; (https://texashistory.unt.edu/ark:/67531/metapth859170/m1/3/: accessed July 18, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .
Door Opener, patent, June 8, 1915; (https://texashistory.unt.edu/ark:/67531/metapth859170/m1/3/: accessed July 18, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .