Grubbing Plow, patent, April 5, 1910; (https://texashistory.unt.edu/ark:/67531/metapth509898/m1/2/: accessed July 4, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .
Grubbing Plow, patent, April 5, 1910; (https://texashistory.unt.edu/ark:/67531/metapth509898/m1/2/: accessed July 4, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .