Weick, Fred E. & Shortal, Joseph A. Wind-Tunnel Research Comparing Lateral Control Devices, Particularly at High Angles of Attack 5: Spoilers and Ailerons on Rectangular Wings, report, June 13, 1932; (https://digital.library.unt.edu/ark:/67531/metadc66095/m1/2/: accessed April 19, 2019), University of North Texas Libraries, Digital Library, digital.library.unt.edu; .