[Letter from Ed de Barbieris to R. Lee Kempner, October 21, 1956], letter, October 21, 1956; (https://texashistory.unt.edu/ark:/67531/metapth1401194/m1/1/: accessed August 15, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .