Drag, patent, May 11, 1920; (https://texashistory.unt.edu/ark:/67531/metapth1256541/m1/2/: accessed July 15, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu; .
Drag, patent, May 11, 1920; (https://texashistory.unt.edu/ark:/67531/metapth1256541/m1/2/: accessed July 15, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu; .