[The Bell H-40 flying over tanks], photograph, April 1958; (https://texashistory.unt.edu/ark:/67531/metadc949898/m1/1/: accessed July 16, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .
[The Bell H-40 flying over tanks], photograph, April 1958; (https://texashistory.unt.edu/ark:/67531/metadc949898/m1/1/: accessed July 16, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .