[Letter from Isaac Herbert Kempner to Gus A. Stirl, April 5, 1954], letter, April 5, 1954; (https://texashistory.unt.edu/ark:/67531/metapth1152633/m1/1/: accessed July 17, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu; .