[Letter from Isaac H. Kempner to E. L. Goar, August 3, 1964], letter, August 3, 1964; (https://texashistory.unt.edu/ark:/67531/metapth1513296/m1/1/: accessed July 16, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu; .