Sayles, John. [Letter from John Sayles to Indian Territory Illuminating Oil Company, August 30, 1940], letter, August 30, 1940; (https://texashistory.unt.edu/ark:/67531/metapth1156896/m1/1/: accessed July 17, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .