Frick, Charles W. & Boyd, John W. Investigation at supersonic speed (M = 1.53) of the pressure distribution over a 63 degrees swept airfoil of biconvex section at zero lift, report, June 10, 1948; (https://digital.library.unt.edu/ark:/67531/metadc57586/m1/1/: accessed October 21, 2018), University of North Texas Libraries, Digital Library, digital.library.unt.edu; .