[Letter from R. M. Armstrong to W. H. Louviere, March 2, 1960], letter, March 2, 1960; (https://texashistory.unt.edu/ark:/67531/metapth1182022/m1/1/: accessed June 21, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .