Marcello, Ronald E.; Kamp, H. W. & Allred, David. Oral History Interview with David Allred, August 9, 1967, book, November 20, 1968; (https://texashistory.unt.edu/ark:/67531/metapth223569/m1/9/: accessed July 16, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu; .