Airfoil Section Data From Tests of 10 Practical-Construction Sections of Helicopter Rotor Blades Submitted by the Sikorsky Aircraft Division, United Aircraft Corporation, report, September 1944; (https://digital.library.unt.edu/ark:/67531/metadc61461/m1/1/: accessed July 16, 2024), University of North Texas Libraries, UNT Digital Library, digital.library.unt.edu; .