[Office Letter from Arthur M. Alpert to Robert Lee Kempner, June 8, 1962], letter, June 8, 1962; (https://texashistory.unt.edu/ark:/67531/metapth1419855/m1/1/: accessed July 16, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu; .