Stallman, David A. [Letter from David A. Stallman to Gordon "Nick" Mueller, August 5, 2009], letter, August 5, 2009; (https://texashistory.unt.edu/ark:/67531/metapth877289/m1/1/: accessed July 16, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .