Alpert, Arthur M. [Memo from Arthur M. Alpert to Harris L. Kempner, 1964], letter, 1964?; (https://texashistory.unt.edu/ark:/67531/metapth1421548/m1/1/: accessed July 16, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .