[Letter from Mario Salas, 1969], letter, 1969; (https://texashistory.unt.edu/ark:/67531/metapth1261439/m1/1/: accessed July 16, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu; .
[Letter from Mario Salas, 1969], letter, 1969; (https://texashistory.unt.edu/ark:/67531/metapth1261439/m1/1/: accessed July 16, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu; .