[Letter from I. H. Kempner to Arthur M. Alpert, June 5, 1962], letter, June 5, 1962; (https://texashistory.unt.edu/ark:/67531/metapth1508354/m1/1/: accessed July 16, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .