Brown, Andrew C.; Dellinger, Gregory F.; El-Mohtar, Chadi; Zornberg, Jorge G. & Gilbert, Robert B. The Long-Term Performance of a Drilled Shaft Retaining Wall in an Expansive Clay, report, October 2013; (https://texashistory.unt.edu/ark:/67531/metapth639712/m1/1/: accessed July 16, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu; .