Kempner, Isaac Herbert, III. [Letter from Denny to Harris Leon Kempner, April 12, 1959], letter, April 12, 1959; (https://texashistory.unt.edu/ark:/67531/metapth1424913/m1/1/: accessed August 15, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .