DGS Newsletter, Number 7, April 1977, periodical, April 1977; (https://texashistory.unt.edu/ark:/67531/metapth1261584/m1/1/: accessed July 10, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .
DGS Newsletter, Number 7, April 1977, periodical, April 1977; (https://texashistory.unt.edu/ark:/67531/metapth1261584/m1/1/: accessed July 10, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .