Well-Drilling Rig., patent, February 3, 1920; (https://texashistory.unt.edu/ark:/67531/metapth1257093/m1/7/: accessed July 16, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu; .
Well-Drilling Rig., patent, February 3, 1920; (https://texashistory.unt.edu/ark:/67531/metapth1257093/m1/7/: accessed July 16, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu; .