Oil Trap, patent, November 22, 1921; (https://texashistory.unt.edu/ark:/67531/metapth1258759/m1/1/: accessed July 11, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .
Oil Trap, patent, November 22, 1921; (https://texashistory.unt.edu/ark:/67531/metapth1258759/m1/1/: accessed July 11, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .