Heaslet, Max A.; Lomax, Harvard & Spreiter, John R. Linearized compressible-flow theory for sonic flight speeds, report, December 12, 1948; (https://digital.library.unt.edu/ark:/67531/metadc65455/m1/1/: accessed April 25, 2024), University of North Texas Libraries, UNT Digital Library, digital.library.unt.edu; .